Commit Graph

20971 Commits

Author SHA1 Message Date
Tony Ambardar ab5d5c9dfd powerpc: fix EDEADLOCK redefinition error in uapi/asm/errno.h
commit 7de21e679e6a789f3729e8402bc440b623a28eae upstream.

A few archs like powerpc have different errno.h values for macros
EDEADLOCK and EDEADLK. In code including both libc and linux versions of
errno.h, this can result in multiple definitions of EDEADLOCK in the
include chain. Definitions to the same value (e.g. seen with mips) do
not raise warnings, but on powerpc there are redefinitions changing the
value, which raise warnings and errors (if using "-Werror").

Guard against these redefinitions to avoid build errors like the following,
first seen cross-compiling libbpf v5.8.9 for powerpc using GCC 8.4.0 with
musl 1.1.24:

  In file included from ../../arch/powerpc/include/uapi/asm/errno.h:5,
                   from ../../include/linux/err.h:8,
                   from libbpf.c:29:
  ../../include/uapi/asm-generic/errno.h:40: error: "EDEADLOCK" redefined [-Werror]
   #define EDEADLOCK EDEADLK

  In file included from toolchain-powerpc_8540_gcc-8.4.0_musl/include/errno.h:10,
                   from libbpf.c:26:
  toolchain-powerpc_8540_gcc-8.4.0_musl/include/bits/errno.h:58: note: this is the location of the previous definition
   #define EDEADLOCK       58

  cc1: all warnings being treated as errors

Cc: Stable <stable@vger.kernel.org>
Reported-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200917135437.1238787-1-Tony.Ambardar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11 14:04:15 +02:00
Mahesh Salgaonkar abf3573ef4 powerpc/eeh: Fix EEH handling for hugepages in ioremap space.
commit 5ae5bc12d0728db60a0aa9b62160ffc038875f1a upstream.

During the EEH MMIO error checking, the current implementation fails to map
the (virtual) MMIO address back to the pci device on radix with hugepage
mappings for I/O. This results into failure to dispatch EEH event with no
recovery even when EEH capability has been enabled on the device.

eeh_check_failure(token)		# token = virtual MMIO address
  addr = eeh_token_to_phys(token);
  edev = eeh_addr_cache_get_dev(addr);
  if (!edev)
	return 0;
  eeh_dev_check_failure(edev);	<= Dispatch the EEH event

In case of hugepage mappings, eeh_token_to_phys() has a bug in virt -> phys
translation that results in wrong physical address, which is then passed to
eeh_addr_cache_get_dev() to match it against cached pci I/O address ranges
to get to a PCI device. Hence, it fails to find a match and the EEH event
never gets dispatched leaving the device in failed state.

The commit 3343962068 ("powerpc/eeh: Handle hugepages in ioremap space")
introduced following logic to translate virt to phys for hugepage mappings:

eeh_token_to_phys():
+	pa = pte_pfn(*ptep);
+
+	/* On radix we can do hugepage mappings for io, so handle that */
+       if (hugepage_shift) {
+               pa <<= hugepage_shift;			<= This is wrong
+               pa |= token & ((1ul << hugepage_shift) - 1);
+       }

This patch fixes the virt -> phys translation in eeh_token_to_phys()
function.

  $ cat /sys/kernel/debug/powerpc/eeh_address_cache
  mem addr range [0x0000040080000000-0x00000400807fffff]: 0030:01:00.1
  mem addr range [0x0000040080800000-0x0000040080ffffff]: 0030:01:00.1
  mem addr range [0x0000040081000000-0x00000400817fffff]: 0030:01:00.0
  mem addr range [0x0000040081800000-0x0000040081ffffff]: 0030:01:00.0
  mem addr range [0x0000040082000000-0x000004008207ffff]: 0030:01:00.1
  mem addr range [0x0000040082080000-0x00000400820fffff]: 0030:01:00.0
  mem addr range [0x0000040082100000-0x000004008210ffff]: 0030:01:00.1
  mem addr range [0x0000040082110000-0x000004008211ffff]: 0030:01:00.0

Above is the list of cached io address ranges of pci 0030:01:00.<fn>.

Before this patch:

Tracing 'arg1' of function eeh_addr_cache_get_dev() during error injection
clearly shows that 'addr=' contains wrong physical address:

   kworker/u16:0-7       [001] ....   108.883775: eeh_addr_cache_get_dev:
	   (eeh_addr_cache_get_dev+0xc/0xf0) addr=0x80103000a510

dmesg shows no EEH recovery messages:

  [  108.563768] bnx2x: [bnx2x_timer:5801(eth2)]MFW seems hanged: drv_pulse (0x9ae) != mcp_pulse (0x7fff)
  [  108.563788] bnx2x: [bnx2x_hw_stats_update:870(eth2)]NIG timer max (4294967295)
  [  108.883788] bnx2x: [bnx2x_acquire_hw_lock:2013(eth1)]lock_status 0xffffffff  resource_bit 0x1
  [  108.884407] bnx2x 0030:01:00.0 eth1: MDC/MDIO access timeout
  [  108.884976] bnx2x 0030:01:00.0 eth1: MDC/MDIO access timeout
  <..>

After this patch:

eeh_addr_cache_get_dev() trace shows correct physical address:

  <idle>-0       [001] ..s.  1043.123828: eeh_addr_cache_get_dev:
	  (eeh_addr_cache_get_dev+0xc/0xf0) addr=0x40080bc7cd8

dmesg logs shows EEH recovery getting triggerred:

  [  964.323980] bnx2x: [bnx2x_timer:5801(eth2)]MFW seems hanged: drv_pulse (0x746f) != mcp_pulse (0x7fff)
  [  964.323991] EEH: Recovering PHB#30-PE#10000
  [  964.324002] EEH: PE location: N/A, PHB location: N/A
  [  964.324006] EEH: Frozen PHB#30-PE#10000 detected
  <..>

Fixes: 3343962068 ("powerpc/eeh: Handle hugepages in ioremap space")
Cc: stable@vger.kernel.org # v5.3+
Reported-by: Dominic DeMarco <ddemarc@us.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161821396263.48361.2796709239866588652.stgit@jupiter
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11 14:04:15 +02:00
Christophe Leroy 57aa4f3091 powerpc: Force inlining of cpu_has_feature() to avoid build failure
[ Upstream commit eed5fae00593ab9d261a0c1ffc1bdb786a87a55a ]

The code relies on constant folding of cpu_has_feature() based
on possible and always true values as defined per
CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE.

Build failure is encountered with for instance
book3e_all_defconfig on kisskb in the AMDGPU driver which uses
cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling
kernel_enable_vsx() or not.

The failure is due to cpu_has_feature() not being inlined with
that configuration with gcc 4.9.

In the same way as commit acdad8fb4a15 ("powerpc: Force inlining of
mmu_has_feature to fix build failure"), for inlining of
cpu_has_feature().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-07 14:47:39 +02:00
Michael Ellerman 614a4ba668 powerpc/4xx: Fix build errors from mfdcr()
[ Upstream commit eead089311f4d935ab5d1d8fbb0c42ad44699ada ]

lkp reported a build error in fsp2.o:

  CC      arch/powerpc/platforms/44x/fsp2.o
  {standard input}:577: Error: unsupported relocation against base

Which comes from:

  pr_err("GESR0: 0x%08x\n", mfdcr(base + PLB4OPB_GESR0));

Where our mfdcr() macro is stringifying "base + PLB4OPB_GESR0", and
passing that to the assembler, which obviously doesn't work.

The mfdcr() macro already checks that the argument is constant using
__builtin_constant_p(), and if not calls the out-of-line version of
mfdcr(). But in this case GCC is smart enough to notice that "base +
PLB4OPB_GESR0" will be constant, even though it's not something we can
immediately stringify into a register number.

Segher pointed out that passing the register number to the inline asm
as a constant would be better, and in fact it fixes the build error,
presumably because it gives GCC a chance to resolve the value.

While we're at it, change mtdcr() similarly.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Feng Tang <feng.tang@intel.com>
Link: https://lore.kernel.org/r/20210218123058.748882-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-30 14:35:20 +02:00
Naveen N. Rao 106fea9ad2 powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()
commit cea15316ceee2d4a51dfdecd79e08a438135416c upstream.

'lis r2,N' is 'addis r2,0,N' and the instruction encoding in the macro
LIS_R2 is incorrect (it currently maps to 'addis r0,r2,N'). Fix the
same.

Fixes: c71b7eff42 ("powerpc: Add ABIv2 support to ppc_function_entry")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210304020411.16796-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 17:03:57 +01:00
Michael Ellerman d92afe30a6 powerpc/64: Fix stack trace not displaying final frame
[ Upstream commit e3de1e291fa58a1ab0f471a4b458eff2514e4b5f ]

In commit bf13718bc57a ("powerpc: show registers when unwinding
interrupt frames") we changed our stack dumping logic to show the full
registers whenever we find an interrupt frame on the stack.

However we didn't notice that on 64-bit this doesn't show the final
frame, ie. the interrupt that brought us in from userspace, whereas on
32-bit it does.

That is due to confusion about the size of that last frame. The code
in show_stack() calls validate_sp(), passing it STACK_INT_FRAME_SIZE
to check the sp is at least that far below the top of the stack.

However on 64-bit that size is too large for the final frame, because
it includes the red zone, but we don't allocate a red zone for the
first frame.

So add a new define that encodes the correct size for 32-bit and
64-bit, and use it in show_stack().

This results in the full trace being shown on 64-bit, eg:

  sysrq: Trigger a crash
  Kernel panic - not syncing: sysrq triggered crash
  CPU: 0 PID: 83 Comm: sh Not tainted 5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty #649
  Call Trace:
  [c00000000a1c3ac0] [c000000000897b70] dump_stack+0xc4/0x114 (unreliable)
  [c00000000a1c3b00] [c00000000014334c] panic+0x178/0x41c
  [c00000000a1c3ba0] [c00000000094e600] sysrq_handle_crash+0x40/0x50
  [c00000000a1c3c00] [c00000000094ef98] __handle_sysrq+0xd8/0x210
  [c00000000a1c3ca0] [c00000000094f820] write_sysrq_trigger+0x100/0x188
  [c00000000a1c3ce0] [c0000000005559dc] proc_reg_write+0x10c/0x1b0
  [c00000000a1c3d10] [c000000000479950] vfs_write+0xf0/0x360
  [c00000000a1c3d60] [c000000000479d9c] ksys_write+0x7c/0x140
  [c00000000a1c3db0] [c00000000002bf5c] system_call_exception+0x19c/0x2c0
  [c00000000a1c3e10] [c00000000000d35c] system_call_common+0xec/0x278
  --- interrupt: c00 at 0x7fff9fbab428
  NIP:  00007fff9fbab428 LR: 000000001000b724 CTR: 0000000000000000
  REGS: c00000000a1c3e80 TRAP: 0c00   Not tainted  (5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty)
  MSR:  900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE>  CR: 22002884  XER: 00000000
  IRQMASK: 0
  GPR00: 0000000000000004 00007fffc3cb8960 00007fff9fc59900 0000000000000001
  GPR04: 000000002a4b32d0 0000000000000002 0000000000000063 0000000000000063
  GPR08: 000000002a4b32d0 0000000000000000 0000000000000000 0000000000000000
  GPR12: 0000000000000000 00007fff9fcca9a0 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 00000000100b8fd0
  GPR20: 000000002a4b3485 00000000100b8f90 0000000000000000 0000000000000000
  GPR24: 000000002a4b0440 00000000100e77b8 0000000000000020 000000002a4b32d0
  GPR28: 0000000000000001 0000000000000002 000000002a4b32d0 0000000000000001
  NIP [00007fff9fbab428] 0x7fff9fbab428
  LR [000000001000b724] 0x1000b724
  --- interrupt: c00

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210209141627.2898485-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:03:43 +01:00
Athira Rajeev 49e38713fa powerpc/perf: Record counter overflow always if SAMPLE_IP is unset
[ Upstream commit d137845c973147a22622cc76c7b0bc16f6206323 ]

While sampling for marked events, currently we record the sample only
if the SIAR valid bit of Sampled Instruction Event Register (SIER) is
set. SIAR_VALID bit is used for fetching the instruction address from
Sampled Instruction Address Register(SIAR). But there are some
usecases, where the user is interested only in the PMU stats at each
counter overflow and the exact IP of the overflow event is not
required. Dropping SIAR invalid samples will fail to record some of
the counter overflows in such cases.

Example of such usecase is dumping the PMU stats (event counts) after
some regular amount of instructions/events from the userspace (ex: via
ptrace). Here counter overflow is indicated to userspace via signal
handler, and captured by monitoring and enabling I/O signaling on the
event file descriptor. In these cases, we expect to get
sample/overflow indication after each specified sample_period.

Perf event attribute will not have PERF_SAMPLE_IP set in the
sample_type if exact IP of the overflow event is not requested. So
while profiling if SAMPLE_IP is not set, just record the counter
overflow irrespective of SIAR_VALID check.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
[mpe: Reflow comment and if formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1612516492-1428-1-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:03:42 +01:00
Nicholas Piggin a54c278fcf powerpc: improve handling of unrecoverable system reset
[ Upstream commit 11cb0a25f71818ca7ab4856548ecfd83c169aa4d ]

If an unrecoverable system reset hits in process context, the system
does not have to panic. Similar to machine check, call nmi_exit()
before die().

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-26-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:03:42 +01:00
Oliver O'Halloran 507b9bce21 powerpc/pci: Add ppc_md.discover_phbs()
[ Upstream commit 5537fcb319d016ce387f818dd774179bc03217f5 ]

On many powerpc platforms the discovery and initalisation of
pci_controllers (PHBs) happens inside of setup_arch(). This is very early
in boot (pre-initcalls) and means that we're initialising the PHB long
before many basic kernel services (slab allocator, debugfs, a real ioremap)
are available.

On PowerNV this causes an additional problem since we map the PHB registers
with ioremap(). As of commit d538aadc27 ("powerpc/ioremap: warn on early
use of ioremap()") a warning is printed because we're using the "incorrect"
API to setup and MMIO mapping in searly boot. The kernel does provide
early_ioremap(), but that is not intended to create long-lived MMIO
mappings and a seperate warning is printed by generic code if
early_ioremap() mappings are "leaked."

This is all fixable with dumb hacks like using early_ioremap() to setup
the initial mapping then replacing it with a real ioremap later on in
boot, but it does raise the question: Why the hell are we setting up the
PHB's this early in boot?

The old and wise claim it's due to "hysterical rasins." Aside from amused
grapes there doesn't appear to be any real reason to maintain the current
behaviour. Already most of the newer embedded platforms perform PHB
discovery in an arch_initcall and between the end of setup_arch() and the
start of initcalls none of the generic kernel code does anything PCI
related. On powerpc scanning PHBs occurs in a subsys_initcall so it should
be possible to move the PHB discovery to a core, postcore or arch initcall.

This patch adds the ppc_md.discover_phbs hook and a core_initcall stub that
calls it. The core_initcalls are the earliest to be called so this will
any possibly issues with dependency between initcalls. This isn't just an
academic issue either since on pseries and PowerNV EEH init occurs in an
arch_initcall and depends on the pci_controllers being available, similarly
the creation of pci_dns occurs at core_initcall_sync (i.e. between core and
postcore initcalls). These problems need to be addressed seperately.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Make discover_phbs() static]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201103043523.916109-1-oohall@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:03:42 +01:00
Christophe Leroy 59a057a891 powerpc/603: Fix protection of user pages mapped with PROT_NONE
commit c119565a15a628efdfa51352f9f6c5186e506a1c upstream.

On book3s/32, page protection is defined by the PP bits in the PTE
which provide the following protection depending on the access
keys defined in the matching segment register:
- PP 00 means RW with key 0 and N/A with key 1.
- PP 01 means RW with key 0 and RO with key 1.
- PP 10 means RW with both key 0 and key 1.
- PP 11 means RO with both key 0 and key 1.

Since the implementation of kernel userspace access protection,
PP bits have been set as follows:
- PP00 for pages without _PAGE_USER
- PP01 for pages with _PAGE_USER and _PAGE_RW
- PP11 for pages with _PAGE_USER and without _PAGE_RW

For kernelspace segments, kernel accesses are performed with key 0
and user accesses are performed with key 1. As PP00 is used for
non _PAGE_USER pages, user can't access kernel pages not flagged
_PAGE_USER while kernel can.

For userspace segments, both kernel and user accesses are performed
with key 0, therefore pages not flagged _PAGE_USER are still
accessible to the user.

This shouldn't be an issue, because userspace is expected to be
accessible to the user. But unlike most other architectures, powerpc
implements PROT_NONE protection by removing _PAGE_USER flag instead of
flagging the page as not valid. This means that pages in userspace
that are not flagged _PAGE_USER shall remain inaccessible.

To get the expected behaviour, just mimic other architectures in the
TLB miss handler by checking _PAGE_USER permission on userspace
accesses as if it was the _PAGE_PRESENT bit.

Note that this problem only is only for 603 cores. The 604+ have
an hash table, and hash_page() function already implement the
verification of _PAGE_USER permission on userspace pages.

Fixes: f342adca3a ("powerpc/32s: Prepare Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Christoph Plattner <christoph.plattner@thalesgroup.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4a0c6e3bb8f0c162457bf54d9bc6fd8d7b55129f.1612160907.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 17:03:33 +01:00
Greg Kurz dcb9579082 powerpc/pseries: Don't enforce MSI affinity with kdump
commit f9619d5e5174867536b7e558683bc4408eab833f upstream.

Depending on the number of online CPUs in the original kernel, it is
likely for CPU #0 to be offline in a kdump kernel. The associated IRQs
in the affinity mappings provided by irq_create_affinity_masks() are
thus not started by irq_startup(), as per-design with managed IRQs.

This can be a problem with multi-queue block devices driven by blk-mq :
such a non-started IRQ is very likely paired with the single queue
enforced by blk-mq during kdump (see blk_mq_alloc_tag_set()). This
causes the device to remain silent and likely hangs the guest at
some point.

This is a regression caused by commit 9ea69a55b3 ("powerpc/pseries:
Pass MSI affinity to irq_create_mapping()"). Note that this only happens
with the XIVE interrupt controller because XICS has a workaround to bypass
affinity, which is activated during kdump with the "noirqdistrib" kernel
parameter.

The issue comes from a combination of factors:
- discrepancy between the number of queues detected by the multi-queue
  block driver, that was used to create the MSI vectors, and the single
  queue mode enforced later on by blk-mq because of kdump (i.e. keeping
  all queues fixes the issue)
- CPU#0 offline (i.e. kdump always succeed with CPU#0)

Given that I couldn't reproduce on x86, which seems to always have CPU#0
online even during kdump, I'm not sure where this should be fixed. Hence
going for another approach : fine-grained affinity is for performance
and we don't really care about that during kdump. Simply revert to the
previous working behavior of ignoring affinity masks in this case only.

Fixes: 9ea69a55b3 ("powerpc/pseries: Pass MSI affinity to irq_create_mapping()")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210215094506.1196119-1-groug@kaod.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 17:03:30 +01:00
Christophe Leroy d5194f7264 powerpc/32s: Add missing call to kuep_lock on syscall entry
commit 57fdfbce89137ae85cd5cef48be168040a47dd13 upstream.

Userspace Execution protection and fast syscall entry were implemented
independently from each other and were both merged in kernel 5.2,
leading to syscall entry missing userspace execution protection.

On syscall entry, execution of user space memory must be
locked in the same way as on exception entry.

Fixes: b86fb88855 ("powerpc/32: implement fast entry for syscalls on non BOOKE")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c65e105b63aaf74f91a14f845bc77192350b84a6.1612796617.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04 10:26:49 +01:00
Cédric Le Goater 14122331b1 powerpc/prom: Fix "ibm,arch-vec-5-platform-support" scan
commit ed5b00a05c2ae95b59adc3442f45944ec632e794 upstream.

The "ibm,arch-vec-5-platform-support" property is a list of pairs of
bytes representing the options and values supported by the platform
firmware. At boot time, Linux scans this list and activates the
available features it recognizes : Radix and XIVE.

A recent change modified the number of entries to loop on and 8 bytes,
4 pairs of { options, values } entries are always scanned. This is
fine on KVM but not on PowerVM which can advertises less. As a
consequence on this platform, Linux reads extra entries pointing to
random data, interprets these as available features and tries to
activate them, leading to a firmware crash in
ibm,client-architecture-support.

Fix that by using the property length of "ibm,arch-vec-5-platform-support".

Fixes: ab91239942 ("powerpc/prom: Remove VLA in prom_check_platform_support()")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210122075029.797013-1-clg@kaod.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04 10:26:46 +01:00
Christophe Leroy ecfae933df powerpc/8xx: Fix software emulation interrupt
[ Upstream commit 903178d0ce6bb30ef80a3604ab9ee2b57869fbc9 ]

For unimplemented instructions or unimplemented SPRs, the 8xx triggers
a "Software Emulation Exception" (0x1000). That interrupt doesn't set
reason bits in SRR1 as the "Program Check Exception" does.

Go through emulation_assist_interrupt() to set REASON_ILLEGAL.

Fixes: fbbcc3bb13 ("powerpc/8xx: Remove SoftwareEmulation()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ad782af87a222efc79cfb06079b0fd23d4224eaf.1612515180.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:33 +01:00
Nathan Lynch ba5c8a0ee6 powerpc/pseries/dlpar: handle ibm, configure-connector delay status
[ Upstream commit 768d70e19ba525debd571b36e6d0ab19956c63d7 ]

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2 (busy, call again), we call
   ibm,configure-connector again immediately without checking whether
   to schedule, which can result in monopolizing the CPU.
2. Extended delay status (9900..9905) goes completely unhandled,
   causing the configuration to unnecessarily terminate.

Fix both of these issues by using rtas_busy_delay().

Fixes: ab519a011c ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:33 +01:00
Christophe Leroy c4c70ac465 powerpc/47x: Disable 256k page size
[ Upstream commit 910a0cb6d259736a0c86e795d4c2f42af8d0d775 ]

PPC47x_TLBE_SIZE isn't defined for 256k pages, leading to a build
break if 256k pages is selected.

So change the kconfig so that 256k pages can't be selected for 47x.

Fixes: e7f75ad01d ("powerpc/47x: Base ppc476 support")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Expand change log to mention build break]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2fed79b1154c872194f98bac4422c23918325e61.1611128938.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:31 +01:00
Cédric Le Goater 8121f35cc6 KVM: PPC: Make the VMX instruction emulation routines static
[ Upstream commit 9236f57a9e51c72ce426ccd2e53e123de7196a0f ]

These are only used locally. It fixes these W=1 compile errors :

../arch/powerpc/kvm/powerpc.c:1521:5: error: no previous prototype for ‘kvmppc_get_vmx_dword’ [-Werror=missing-prototypes]
 1521 | int kvmppc_get_vmx_dword(struct kvm_vcpu *vcpu, int index, u64 *val)
      |     ^~~~~~~~~~~~~~~~~~~~
../arch/powerpc/kvm/powerpc.c:1539:5: error: no previous prototype for ‘kvmppc_get_vmx_word’ [-Werror=missing-prototypes]
 1539 | int kvmppc_get_vmx_word(struct kvm_vcpu *vcpu, int index, u64 *val)
      |     ^~~~~~~~~~~~~~~~~~~
../arch/powerpc/kvm/powerpc.c:1557:5: error: no previous prototype for ‘kvmppc_get_vmx_hword’ [-Werror=missing-prototypes]
 1557 | int kvmppc_get_vmx_hword(struct kvm_vcpu *vcpu, int index, u64 *val)
      |     ^~~~~~~~~~~~~~~~~~~~
../arch/powerpc/kvm/powerpc.c:1575:5: error: no previous prototype for ‘kvmppc_get_vmx_byte’ [-Werror=missing-prototypes]
 1575 | int kvmppc_get_vmx_byte(struct kvm_vcpu *vcpu, int index, u64 *val)
      |     ^~~~~~~~~~~~~~~~~~~

Fixes: acc9eb9305 ("KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction mmio emulation with analyse_instr() input")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210104143206.695198-19-clg@kaod.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 10:26:31 +01:00
Thomas Gleixner 4f5416710e vmlinux.lds.h: Create section for protection against instrumentation
[ Upstream commit 6553896666 ]

Some code pathes, especially the low level entry code, must be protected
against instrumentation for various reasons:

 - Low level entry code can be a fragile beast, especially on x86.

 - With NO_HZ_FULL RCU state needs to be established before using it.

Having a dedicated section for such code allows to validate with tooling
that no unsafe functions are invoked.

Add the .noinstr.text section and the noinstr attribute to mark
functions. noinstr implies notrace. Kprobes will gain a section check
later.

Provide also a set of markers: instrumentation_begin()/end()

These are used to mark code inside a noinstr function which calls
into regular instrumentable text section as safe.

The instrumentation markers are only active when CONFIG_DEBUG_ENTRY is
enabled as the end marker emits a NOP to prevent the compiler from merging
the annotation points. This means the objtool verification requires a
kernel compiled with this option.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134100.075416272@linutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-17 10:35:16 +01:00
Ariel Marcovitch 485e0255c1 powerpc: Fix alignment bug within the init sections
[ Upstream commit 2225a8dda263edc35a0e8b858fe2945cf6240fde ]

This is a bug that causes early crashes in builds with an .exit.text
section smaller than a page and an .init.text section that ends in the
beginning of a physical page (this is kinda random, which might
explain why this wasn't really encountered before).

The init sections are ordered like this:
  .init.text
  .exit.text
  .init.data

Currently, these sections aren't page aligned.

Because the init code might become read-only at runtime and because
the .init.text section can potentially reside on the same physical
page as .init.data, the beginning of .init.data might be mapped
read-only along with .init.text.

Then when the kernel tries to modify a variable in .init.data (like
kthreadd_done, used in kernel_init()) the kernel panics.

To avoid this, make _einittext page aligned and also align .exit.text
to make sure .init.data is always seperated from the text segments.

Fixes: 060ef9d89d ("powerpc32: PAGE_EXEC required for inittext")
Signed-off-by: Ariel Marcovitch <ariel.marcovitch@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210102201156.10805-1-ariel.marcovitch@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27 11:47:47 +01:00
Youling Tang 5625c3da71 powerpc: Use the common INIT_DATA_SECTION macro in vmlinux.lds.S
[ Upstream commit fdcfeaba38e5b183045f5b079af94f97658eabe6 ]

Use the common INIT_DATA_SECTION rule for the linker script in an effort
to regularize the linker script.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1604487550-20040-1-git-send-email-tangyouling@loongson.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27 11:47:46 +01:00
Nathan Chancellor c511f27e13 powerpc: Handle .text.{hot,unlikely}.* in linker script
commit 3ce47d95b7346dcafd9bed3556a8d072cb2b8571 upstream.

Commit eff8728fe6 ("vmlinux.lds.h: Add PGO and AutoFDO input
sections") added ".text.unlikely.*" and ".text.hot.*" due to an LLVM
change [1].

After another LLVM change [2], these sections are seen in some PowerPC
builds, where there is a orphan section warning then build failure:

$ make -skj"$(nproc)" \
       ARCH=powerpc CROSS_COMPILE=powerpc64le-linux-gnu- LLVM=1 O=out \
       distclean powernv_defconfig zImage.epapr
ld.lld: warning: kernel/built-in.a(panic.o):(.text.unlikely.) is being placed in '.text.unlikely.'
...
ld.lld: warning: address (0xc000000000009314) of section .text is not a multiple of alignment (256)
...
ERROR: start_text address is c000000000009400, should be c000000000008000
ERROR: try to enable LD_HEAD_STUB_CATCH config option
ERROR: see comments in arch/powerpc/tools/head_check.sh
...

Explicitly handle these sections like in the main linker script so
there is no more build failure.

[1]: https://reviews.llvm.org/D79600
[2]: https://reviews.llvm.org/D92493

Fixes: 83a092cf95 ("powerpc: Link warning for orphan sections")
Cc: stable@vger.kernel.org
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/1218
Link: https://lore.kernel.org/r/20210104205952.1399409-1-natechancellor@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12 20:16:17 +01:00
Qinglang Miao 22f815627c powerpc: sysdev: add missing iounmap() on error in mpic_msgr_probe()
[ Upstream commit ffa1797040c5da391859a9556be7b735acbe1242 ]

I noticed that iounmap() of msgr_block_addr before return from
mpic_msgr_probe() in the error handling case is missing. So use
devm_ioremap() instead of just ioremap() when remapping the message
register block, so the mapping will be automatically released on
probe failure.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201028091551.136400-1-miaoqinglang@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06 14:48:39 +01:00
Christophe Leroy ee78e7d93e powerpc/bitops: Fix possible undefined behaviour with fls() and fls64()
[ Upstream commit 1891ef21d92c4801ea082ee8ed478e304ddc6749 ]

fls() and fls64() are using __builtin_ctz() and _builtin_ctzll().
On powerpc, those builtins trivially use ctlzw and ctlzd power
instructions.

Allthough those instructions provide the expected result with
input argument 0, __builtin_ctz() and __builtin_ctzll() are
documented as undefined for value 0.

The easiest fix would be to use fls() and fls64() functions
defined in include/asm-generic/bitops/builtin-fls.h and
include/asm-generic/bitops/fls64.h, but GCC output is not optimal:

00000388 <testfls>:
 388:   2c 03 00 00     cmpwi   r3,0
 38c:   41 82 00 10     beq     39c <testfls+0x14>
 390:   7c 63 00 34     cntlzw  r3,r3
 394:   20 63 00 20     subfic  r3,r3,32
 398:   4e 80 00 20     blr
 39c:   38 60 00 00     li      r3,0
 3a0:   4e 80 00 20     blr

000003b0 <testfls64>:
 3b0:   2c 03 00 00     cmpwi   r3,0
 3b4:   40 82 00 1c     bne     3d0 <testfls64+0x20>
 3b8:   2f 84 00 00     cmpwi   cr7,r4,0
 3bc:   38 60 00 00     li      r3,0
 3c0:   4d 9e 00 20     beqlr   cr7
 3c4:   7c 83 00 34     cntlzw  r3,r4
 3c8:   20 63 00 20     subfic  r3,r3,32
 3cc:   4e 80 00 20     blr
 3d0:   7c 63 00 34     cntlzw  r3,r3
 3d4:   20 63 00 40     subfic  r3,r3,64
 3d8:   4e 80 00 20     blr

When the input of fls(x) is a constant, just check x for nullity and
return either 0 or __builtin_clz(x). Otherwise, use cntlzw instruction
directly.

For fls64() on PPC64, do the same but with __builtin_clzll() and
cntlzd instruction. On PPC32, lets take the generic fls64() which
will use our fls(). The result is as expected:

00000388 <testfls>:
 388:   7c 63 00 34     cntlzw  r3,r3
 38c:   20 63 00 20     subfic  r3,r3,32
 390:   4e 80 00 20     blr

000003a0 <testfls64>:
 3a0:   2c 03 00 00     cmpwi   r3,0
 3a4:   40 82 00 10     bne     3b4 <testfls64+0x14>
 3a8:   7c 83 00 34     cntlzw  r3,r4
 3ac:   20 63 00 20     subfic  r3,r3,32
 3b0:   4e 80 00 20     blr
 3b4:   7c 63 00 34     cntlzw  r3,r3
 3b8:   20 63 00 40     subfic  r3,r3,64
 3bc:   4e 80 00 20     blr

Fixes: 2fcff790dc ("powerpc: Use builtin functions for fls()/__fls()/fls64()")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/348c2d3f19ffcff8abe50d52513f989c4581d000.1603375524.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06 14:48:36 +01:00
David Hildenbrand a89b91fcb0 powerpc/powernv/memtrace: Fix crashing the kernel when enabling concurrently
commit d6718941a2767fb383e105d257d2105fe4f15f0e upstream.

It's very easy to crash the kernel right now by simply trying to
enable memtrace concurrently, hammering on the "enable" interface

loop.sh:
  #!/bin/bash

  dmesg --console-off

  while true; do
          echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable
  done

[root@localhost ~]# loop.sh &
[root@localhost ~]# loop.sh &

Resulting quickly in a kernel crash. Let's properly protect using a
mutex.

Fixes: 9d5171a8f2 ("powerpc/powernv: Enable removal of memory for in memory tracing")
Cc: stable@vger.kernel.org# v4.14+
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201111145322.15793-3-david@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
David Hildenbrand 45bf367c85 powerpc/powernv/memtrace: Don't leak kernel memory to user space
commit c74cf7a3d59a21b290fe0468f5b470d0b8ee37df upstream.

We currently leak kernel memory to user space, because memory
offlining doesn't do any implicit clearing of memory and we are
missing explicit clearing of memory.

Let's keep it simple and clear pages before removing the linear
mapping.

Reproduced in QEMU/TCG with 10 GiB of main memory:
  [root@localhost ~]# dd obs=9G if=/dev/urandom of=/dev/null
  [... wait until "free -m" used counter no longer changes and cancel]
  19665802+0 records in
  1+0 records out
  9663676416 bytes (9.7 GB, 9.0 GiB) copied, 135.548 s, 71.3 MB/s
  [root@localhost ~]# cat /sys/devices/system/memory/block_size_bytes
  40000000
  [root@localhost ~]# echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable
  [  402.978663][ T1086] page:000000001bc4bc74 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24900
  [  402.980063][ T1086] flags: 0x7ffff000001000(reserved)
  [  402.980415][ T1086] raw: 007ffff000001000 c00c000000924008 c00c000000924008 0000000000000000
  [  402.980627][ T1086] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
  [  402.980845][ T1086] page dumped because: unmovable page
  [  402.989608][ T1086] Offlined Pages 16384
  [  403.324155][ T1086] memtrace: Allocated trace memory on node 0 at 0x0000000200000000

Before this patch:
  [root@localhost ~]# hexdump -C /sys/kernel/debug/powerpc/memtrace/00000000/trace  | head
  00000000  c8 25 72 51 4d 26 36 c5  5c c2 56 15 d5 1a cd 10  |.%rQM&6.\.V.....|
  00000010  19 b9 50 b2 cb e3 60 b8  ec 0a f3 ec 4b 3c 39 f0  |..P...`.....K<9.|$
  00000020  4e 5a 4c cf bd 26 19 ff  37 79 13 67 24 b7 b8 57  |NZL..&..7y.g$..W|$
  00000030  98 3e f5 be 6f 14 6a bd  a4 52 bc 6e e9 e0 c1 5d  |.>..o.j..R.n...]|$
  00000040  76 b3 ae b5 88 d7 da e3  64 23 85 2c 10 88 07 b6  |v.......d#.,....|$
  00000050  9a d8 91 de f7 50 27 69  2e 64 9c 6f d3 19 45 79  |.....P'i.d.o..Ey|$
  00000060  6a 6f 8a 61 71 19 1f c7  f1 df 28 26 ca 0f 84 55  |jo.aq.....(&...U|$
  00000070  01 3f be e4 e2 e1 da ff  7b 8c 8e 32 37 b4 24 53  |.?......{..27.$S|$
  00000080  1b 70 30 45 56 e6 8c c4  0e b5 4c fb 9f dd 88 06  |.p0EV.....L.....|$
  00000090  ef c4 18 79 f1 60 b1 5c  79 59 4d f4 36 d7 4a 5c  |...y.`.\yYM.6.J\|$

After this patch:
  [root@localhost ~]# hexdump -C /sys/kernel/debug/powerpc/memtrace/00000000/trace  | head
  00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
  *
  40000000

Fixes: 9d5171a8f2 ("powerpc/powernv: Enable removal of memory for in memory tracing")
Cc: stable@vger.kernel.org # v4.14+
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201111145322.15793-2-david@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
Alexey Kardashevskiy 59334d821e powerpc/powernv/npu: Do not attempt NPU2 setup on POWER8NVL NPU
commit b1198a88230f2ce50c271e22b82a8b8610b2eea9 upstream.

We execute certain NPU2 setup code (such as mapping an LPID to a device
in NPU2) unconditionally if an Nvlink bridge is detected. However this
cannot succeed on POWER8NVL machines and errors appear in dmesg. This is
harmless as skiboot returns an error and the only place we check it is
vfio-pci but that code does not get called on P8+ either.

This adds a check if pnv_npu2_xxx helpers are called on a machine with
NPU2 which initializes pnv_phb::npu in pnv_npu2_init();
pnv_phb::npu==NULL on POWER8/NVL (Naples).

While at this, fix NULL derefencing in pnv_npu_peers_take_ownership/
pnv_npu_peers_release_ownership which occurs when GPUs on mentioned P8s
cause EEH which happens if "vfio-pci" disables devices using
the D3 power state; the vfio-pci's disable_idle_d3 module parameter
controls this and must be set on Naples. The EEH handling clears
the entire pnv_ioda_pe struct in pnv_ioda_free_pe() hence
the NULL derefencing. We cannot recover from that but at least we stop
crashing.

Tested on
- POWER9 pvr=004e1201, Ubuntu 19.04 host, Ubuntu 18.04 vm,
  NVIDIA GV100 10de:1db1 driver 418.39
- POWER8 pvr=004c0100, RHEL 7.6 host, Ubuntu 16.10 vm,
  NVIDIA P100 10de:15f9 driver 396.47

Fixes: 1b785611e1 ("powerpc/powernv/npu: Add release_ownership hook")
Cc: stable@vger.kernel.org # 5.0
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201122073828.15446-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
Christophe Leroy c7f66ad880 powerpc/mm: Fix verification of MMU_FTR_TYPE_44x
commit 17179aeb9d34cc81e1a4ae3f85e5b12b13a1f8d0 upstream.

MMU_FTR_TYPE_44x cannot be checked by cpu_has_feature()

Use mmu_has_feature() instead

Fixes: 23eb7f560a ("powerpc: Convert flush_icache_range & friends to C")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ceede82fadf37f3b8275e61fcf8cf29a3e2ec7fe.1602351011.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
Christophe Leroy 32e29541b5 powerpc/8xx: Fix early debug when SMC1 is relocated
commit 1e78f723d6a52966bfe3804209dbf404fdc9d3bb upstream.

When SMC1 is relocated and early debug is selected, the
board hangs is ppc_md.setup_arch(). This is because ones
the microcode has been loaded and SMC1 relocated, early
debug writes in the weed.

To allow smooth continuation, the SMC1 parameter RAM set up
by the bootloader have to be copied into the new location.

Fixes: 43db76f418 ("powerpc/8xx: Add microcode patch to move SMC parameter RAM.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b2f71f39eca543f1e4ec06596f09a8b12235c701.1607076683.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
Christophe Leroy 15c9e56b41 powerpc/xmon: Change printk() to pr_cont()
commit 7c6c86b36a36dd4a13d30bba07718e767aa2e7a1 upstream.

Since some time now, printk() adds carriage return, leading to
unusable xmon output if there is no udbg backend available:

  [   54.288722] sysrq: Entering xmon
  [   54.292209] Vector: 0  at [cace3d2c]
  [   54.292274]     pc:
  [   54.292331] c0023650
  [   54.292468] : xmon+0x28/0x58
  [   54.292519]
  [   54.292574]     lr:
  [   54.292630] c0023724
  [   54.292749] : sysrq_handle_xmon+0xa4/0xfc
  [   54.292801]
  [   54.292867]     sp: cace3de8
  [   54.292931]    msr: 9032
  [   54.292999]   current = 0xc28d0000
  [   54.293072]     pid   = 377, comm = sh
  [   54.293157] Linux version 5.10.0-rc6-s3k-dev-01364-gedf13f0ccd76-dirty (root@po17688vm.idsi0.si.c-s.fr) (powerpc64-linux-gcc (GCC) 10.1.0, GNU ld (GNU Binutils) 2.34) #4211 PREEMPT Fri Dec 4 09:32:11 UTC 2020
  [   54.293287] enter ? for help
  [   54.293470] [cace3de8]
  [   54.293532] c0023724
  [   54.293654]  sysrq_handle_xmon+0xa4/0xfc
  [   54.293711]  (unreliable)
  ...
  [   54.296002]
  [   54.296159] --- Exception: c01 (System Call) at
  [   54.296217] 0fd4e784
  [   54.296303]
  [   54.296375] SP (7fca6ff0) is in userspace
  [   54.296431] mon>
  [   54.296484]  <no input ...>

Use pr_cont() instead.

Fixes: 4bcc595ccd ("printk: reinstate KERN_CONT for printing continuation lines")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Mention that it only happens when udbg is not available]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c8a6ec704416ecd5ff2bd26213c9bc026bdd19de.1607077340.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:39 +01:00
Christophe Leroy c7b89d0d71 powerpc/feature: Add CPU_FTR_NOEXECUTE to G2_LE
commit 197493af414ee22427be3343637ac290a791925a upstream.

G2_LE has a 603 core, add CPU_FTR_NOEXECUTE.

Fixes: 385e89d5b2 ("powerpc/mm: add exec protection on powerpc 603")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/39a530ee41d83f49747ab3af8e39c056450b9b4d.1602489653.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:38 +01:00
Tyrel Datwyler 0f157acd43 powerpc/rtas: Fix typo of ibm,open-errinjct in RTAS filter
commit f10881a46f8914428110d110140a455c66bdf27b upstream.

Commit bd59380c5b ("powerpc/rtas: Restrict RTAS requests from userspace")
introduced the following error when invoking the errinjct userspace
tool:

  [root@ltcalpine2-lp5 librtas]# errinjct open
  [327884.071171] sys_rtas: RTAS call blocked - exploit attempt?
  [327884.071186] sys_rtas: token=0x26, nargs=0 (called by errinjct)
  errinjct: Could not open RTAS error injection facility
  errinjct: librtas: open: Unexpected I/O error

The entry for ibm,open-errinjct in rtas_filter array has a typo where
the "j" is omitted in the rtas call name. After fixing this typo the
errinjct tool functions again as expected.

  [root@ltcalpine2-lp5 linux]# errinjct open
  RTAS error injection facility open, token = 1

Fixes: bd59380c5b ("powerpc/rtas: Restrict RTAS requests from userspace")
Cc: stable@vger.kernel.org
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201208195434.8289-1-tyreld@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:38 +01:00
Mathieu Desnoyers 30a58a3f7c powerpc: Fix incorrect stw{, ux, u, x} instructions in __set_pte_at
commit d85be8a49e733dcd23674aa6202870d54bf5600d upstream.

The placeholder for instruction selection should use the second
argument's operand, which is %1, not %0. This could generate incorrect
assembly code if the memory addressing of operand %0 is a different
form from that of operand %1.

Also remove the %Un placeholder because having %Un placeholders
for two operands which are based on the same local var (ptep) doesn't
make much sense. By the way, it doesn't change the current behaviour
because "<>" constraint is missing for the associated "=m".

[chleroy: revised commit log iaw segher's comments and removed %U0]

Fixes: 9bf2b5cdc5 ("powerpc: Fixes for CONFIG_PTE_64BIT for SMP support")
Cc: <stable@vger.kernel.org> # v2.6.28+
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/96354bd77977a6a933fe9020da57629007fdb920.1603358942.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:38 +01:00
Athira Rajeev f26f0e7770 powerpc/perf: Exclude kernel samples while counting events in user space.
commit aa8e21c053d72b6639ea5a7f1d3a1d0209534c94 upstream.

Perf event attritube supports exclude_kernel flag to avoid
sampling/profiling in supervisor state (kernel). Based on this event
attr flag, Monitor Mode Control Register bit is set to freeze on
supervisor state. But sometimes (due to hardware limitation), Sampled
Instruction Address Register (SIAR) locks on to kernel address even
when freeze on supervisor is set. Patch here adds a check to drop
those samples.

Cc: stable@vger.kernel.org
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1606289215-1433-1-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:35 +01:00
Christophe Leroy 3f72486cec powerpc/mm: sanity_check_fault() should work for all, not only BOOK3S
[ Upstream commit 7ceb40027e19567a0a066e3b380cc034cdd9a124 ]

The verification and message introduced by commit 374f3f5979
("powerpc/mm/hash: Handle user access of kernel address gracefully")
applies to all platforms, it should not be limited to BOOK3S.

Make the BOOK3S version of sanity_check_fault() the one for all,
and bail out earlier if not BOOK3S.

Fixes: 374f3f5979 ("powerpc/mm/hash: Handle user access of kernel address gracefully")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fe199d5af3578d3bf80035d203a94d742a7a28af.1607491748.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:22 +01:00
Nathan Lynch ef55a3c384 powerpc/pseries/hibernation: remove redundant cacheinfo update
[ Upstream commit b866459489fe8ef0e92cde3cbd6bbb1af6c4e99b ]

Partitions with cache nodes in the device tree can encounter the
following warning on resume:

CPU 0 already accounted in PowerPC,POWER9@0(Data)
WARNING: CPU: 0 PID: 3177 at arch/powerpc/kernel/cacheinfo.c:197 cacheinfo_cpu_online+0x640/0x820

These calls to cacheinfo_cpu_offline/online have been redundant since
commit e610a466d1 ("powerpc/pseries/mobility: rebuild cacheinfo
hierarchy post-migration").

Fixes: e610a466d1 ("powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201207215200.1785968-25-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:21 +01:00
Nathan Lynch c4115721d1 powerpc/pseries/hibernation: drop pseries_suspend_begin() from suspend ops
[ Upstream commit 52719fce3f4c7a8ac9eaa191e8d75a697f9fbcbc ]

There are three ways pseries_suspend_begin() can be reached:

1. When "mem" is written to /sys/power/state:

kobj_attr_store()
-> state_store()
  -> pm_suspend()
    -> suspend_devices_and_enter()
      -> pseries_suspend_begin()

This never works because there is no way to supply a valid stream id
using this interface, and H_VASI_STATE is called with a stream id of
zero. So this call path is useless at best.

2. When a stream id is written to /sys/devices/system/power/hibernate.
pseries_suspend_begin() is polled directly from store_hibernate()
until the stream is in the "Suspending" state (i.e. the platform is
ready for the OS to suspend execution):

dev_attr_store()
-> store_hibernate()
  -> pseries_suspend_begin()

3. When a stream id is written to /sys/devices/system/power/hibernate
(continued). After #2, pseries_suspend_begin() is called once again
from the pm core:

dev_attr_store()
-> store_hibernate()
  -> pm_suspend()
    -> suspend_devices_and_enter()
      -> pseries_suspend_begin()

This is redundant because the VASI suspend state is already known to
be Suspending.

The begin() callback of platform_suspend_ops is optional, so we can
simply remove that assignment with no loss of function.

Fixes: 32d8ad4e62 ("powerpc/pseries: Partition hibernation support")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201207215200.1785968-18-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:21 +01:00
Jordan Niethe 40f9ac2b02 powerpc/64: Fix an EMIT_BUG_ENTRY in head_64.S
[ Upstream commit fe18a35e685c9bdabc8b11b3e19deb85a068b75d ]

Commit 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard
trap") added an EMIT_BUG_ENTRY for the trap after the branch to
start_kernel(). The EMIT_BUG_ENTRY was for the address "0b", however the
trap was not labeled with "0". Hence the address used for bug is in
relative_toc() where the previous "0" label is. Label the trap as "0" so
the correct address is used.

Fixes: 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard trap")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201130004404.30953-1-jniethe5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:17 +01:00
Athira Rajeev 4968cc5ed0 powerpc/perf: Fix crash with is_sier_available when pmu is not set
[ Upstream commit f75e7d73bdf73f07b0701a6d21c111ef5d9021dd ]

On systems without any specific PMU driver support registered, running
'perf record' with —intr-regs  will crash ( perf record -I <workload> ).

The relevant portion from crash logs and Call Trace:

Unable to handle kernel paging request for data at address 0x00000068
Faulting instruction address: 0xc00000000013eb18
Oops: Kernel access of bad area, sig: 11 [#1]
CPU: 2 PID: 13435 Comm: kill Kdump: loaded Not tainted 4.18.0-193.el8.ppc64le #1
NIP:  c00000000013eb18 LR: c000000000139f2c CTR: c000000000393d80
REGS: c0000004a07ab4f0 TRAP: 0300   Not tainted  (4.18.0-193.el8.ppc64le)
NIP [c00000000013eb18] is_sier_available+0x18/0x30
LR [c000000000139f2c] perf_reg_value+0x6c/0xb0
Call Trace:
[c0000004a07ab770] [c0000004a07ab7c8] 0xc0000004a07ab7c8 (unreliable)
[c0000004a07ab7a0] [c0000000003aa77c] perf_output_sample+0x60c/0xac0
[c0000004a07ab840] [c0000000003ab3f0] perf_event_output_forward+0x70/0xb0
[c0000004a07ab8c0] [c00000000039e208] __perf_event_overflow+0x88/0x1a0
[c0000004a07ab910] [c00000000039e42c] perf_swevent_hrtimer+0x10c/0x1d0
[c0000004a07abc50] [c000000000228b9c] __hrtimer_run_queues+0x17c/0x480
[c0000004a07abcf0] [c00000000022aaf4] hrtimer_interrupt+0x144/0x520
[c0000004a07abdd0] [c00000000002a864] timer_interrupt+0x104/0x2f0
[c0000004a07abe30] [c0000000000091c4] decrementer_common+0x114/0x120

When perf record session is started with "-I" option, capturing registers
on each sample calls is_sier_available() to check for the
SIER (Sample Instruction Event Register) availability in the platform.
This function in core-book3s accesses 'ppmu->flags'. If a platform specific
PMU driver is not registered, ppmu is set to NULL and accessing its
members results in a crash. Fix the crash by returning false in
is_sier_available() if ppmu is not set.

Fixes: 333804dc3b ("powerpc/perf: Update perf_regs structure to include SIER")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1606185640-1720-1-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:17 +01:00
Christophe Leroy 0789349204 powerpc/feature: Fix CPU_FTRS_ALWAYS by removing CPU_FTRS_GENERIC_32
[ Upstream commit 78665179e569c7e1fe102fb6c21d0f5b6951f084 ]

On 8xx, we get the following features:

[    0.000000] cpu_features      = 0x0000000000000100
[    0.000000]   possible        = 0x0000000000000120
[    0.000000]   always          = 0x0000000000000000

This is not correct. As CONFIG_PPC_8xx is mutually exclusive with all
other configurations, the three lines should be equal.

The problem is due to CPU_FTRS_GENERIC_32 which is taken when
CONFIG_BOOK3S_32 is NOT selected. This CPU_FTRS_GENERIC_32 is
pointless because there is no generic configuration supporting
all 32 bits but book3s/32.

Remove this pointless generic features definition to unbreak the
calculation of 'possible' features and 'always' features.

Fixes: 76bc080ef5 ("[POWERPC] Make default cputable entries reflect selected CPU family")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/76a85f30bf981d1aeaae00df99321235494da254.1604426550.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:10 +01:00
Ard Biesheuvel 90b39366d8 powerpc: Avoid broken GCC __attribute__((optimize))
[ Upstream commit a7223f5bfcaeade4a86d35263493bcda6c940891 ]

Commit 7053f80d96 ("powerpc/64: Prevent stack protection in early
boot") introduced a couple of uses of __attribute__((optimize)) with
function scope, to disable the stack protector in some early boot
code.

Unfortunately, and this is documented in the GCC man pages [0],
overriding function attributes for optimization is broken, and is only
supported for debug scenarios, not for production: the problem appears
to be that setting GCC -f flags using this method will cause it to
forget about some or all other optimization settings that have been
applied.

So the only safe way to disable the stack protector is to disable it
for the entire source file.

[0] https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html

Fixes: 7053f80d96 ("powerpc/64: Prevent stack protection in early boot")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
[mpe: Drop one remaining use of __nostackprotector, reported by snowpatch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201028080433.26799-1-ardb@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:09 +01:00
Jordan Niethe 4e20cee19c powerpc/64: Set up a kernel stack for secondaries before cpu_restore()
[ Upstream commit 3c0b976bf20d236c57adcefa80f86a0a1d737727 ]

Currently in generic_secondary_smp_init(), cur_cpu_spec->cpu_restore()
is called before a stack has been set up in r1. This was previously fine
as the cpu_restore() functions were implemented in assembly and did not
use a stack. However commit 5a61ef74f2 ("powerpc/64s: Support new
device tree binding for discovering CPU features") used
__restore_cpu_cpufeatures() as the cpu_restore() function for a
device-tree features based cputable entry. This is a C function and
hence uses a stack in r1.

generic_secondary_smp_init() is entered on the secondary cpus via the
primary cpu using the OPAL call opal_start_cpu(). In OPAL, each hardware
thread has its own stack. The OPAL call is ran in the primary's hardware
thread. During the call, a job is scheduled on a secondary cpu that will
start executing at the address of generic_secondary_smp_init().  Hence
the value that will be left in r1 when the secondary cpu enters the
kernel is part of that secondary cpu's individual OPAL stack. This means
that __restore_cpu_cpufeatures() will write to that OPAL stack. This is
not horribly bad as each hardware thread has its own stack and the call
that enters the kernel from OPAL never returns, but it is still wrong
and should be corrected.

Create the temp kernel stack before calling cpu_restore().

As noted by mpe, for a kexec boot, the secondary CPUs are released from
the spin loop at address 0x60 by smp_release_cpus() and then jump to
generic_secondary_smp_init(). The call to smp_release_cpus() is in
setup_arch(), and it comes before the call to emergency_stack_init().
emergency_stack_init() allocates an emergency stack in the PACA for each
CPU.  This address in the PACA is what is used to set up the temp kernel
stack in generic_secondary_smp_init(). Move releasing the secondary CPUs
to after the PACAs have been allocated an emergency stack, otherwise the
PACA stack pointer will contain garbage and hence the temp kernel stack
created from it will be broken.

Fixes: 5a61ef74f2 ("powerpc/64s: Support new device tree binding for discovering CPU features")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014072837.24539-1-jniethe5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:04 +01:00
Michael Ellerman acac3f7d7d powerpc: Drop -me200 addition to build flags
[ Upstream commit e02152ba28 ]

Currently a build with CONFIG_E200=y will fail with:

  Error: invalid switch -me200
  Error: unrecognized option -me200

Upstream binutils has never supported an -me200 option. Presumably it
was supported at some point by either a fork or Freescale internal
binutils.

We can't support code that we can't even build test, so drop the
addition of -me200 to the build flags, so we can at least build with
CONFIG_E200=y.

Reported-by: Németh Márton <nm127@freemail.hu>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Scott Wood <oss@buserror.net>
Link: https://lore.kernel.org/r/20201116120913.165317-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-16 10:56:55 +01:00
Laurent Vivier 7eb514087c powerpc/pseries: Pass MSI affinity to irq_create_mapping()
commit 9ea69a55b3 upstream.

With virtio multiqueue, normally each queue IRQ is mapped to a CPU.

Commit 0d9f0a52c8 ("virtio_scsi: use virtio IRQ affinity") exposed
an existing shortcoming of the arch code by moving virtio_scsi to
the automatic IRQ affinity assignment.

The affinity is correctly computed in msi_desc but this is not applied
to the system IRQs.

It appears the affinity is correctly passed to rtas_setup_msi_irqs() but
lost at this point and never passed to irq_domain_alloc_descs()
(see commit 06ee6d571f ("genirq: Add affinity hint to irq allocation"))
because irq_create_mapping() doesn't take an affinity parameter.

Use the new irq_create_mapping_affinity() function, which allows to forward
the affinity setting from rtas_setup_msi_irqs() to irq_domain_alloc_descs().

With this change, the virtqueues are correctly dispatched between the CPUs
on pseries.

Fixes: e75eafb9b0 ("genirq/msi: Switch to new irq spreading infrastructure")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201126082852.1178497-3-lvivier@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11 13:23:30 +01:00
Nicholas Piggin 6466119452 powerpc/64s/powernv: Fix memory corruption when saving SLB entries on MCE
commit a1ee281170 upstream.

This can be hit by an HPT guest running on an HPT host and bring down
the host, so it's quite important to fix.

Fixes: 7290f3b3d3 ("powerpc/64s/powernv: machine check dump SLB contents")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-2-npiggin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11 13:23:30 +01:00
Stephen Rothwell 22f821fa5c powerpc/64s: Fix allnoconfig build since uaccess flush
[ Upstream commit b6b79dd530 ]

Using DECLARE_STATIC_KEY_FALSE needs linux/jump_table.h.

Otherwise the build fails with eg:

  arch/powerpc/include/asm/book3s/64/kup-radix.h:66:1: warning: data definition has no type or storage class
     66 | DECLARE_STATIC_KEY_FALSE(uaccess_flush_key);

Fixes: 9a32a7e78b ("powerpc/64s: flush L1D after user accesses")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[mpe: Massage change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201123184016.693fe464@canb.auug.org.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-02 08:49:52 +01:00
Arnd Bergmann 1bef5f25a6 arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed
[ Upstream commit cef3970381 ]

Stefan Agner reported a bug when using zsram on 32-bit Arm machines
with RAM above the 4GB address boundary:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = a27bd01c
  [00000000] *pgd=236a0003, *pmd=1ffa64003
  Internal error: Oops: 207 [#1] SMP ARM
  Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet
  CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1
  Hardware name: BCM2711
  PC is at zs_map_object+0x94/0x338
  LR is at zram_bvec_rw.constprop.0+0x330/0xa64
  pc : [<c0602b38>]    lr : [<c0bda6a0>]    psr: 60000013
  sp : e376bbe0  ip : 00000000  fp : c1e2921c
  r10: 00000002  r9 : c1dda730  r8 : 00000000
  r7 : e8ff7a00  r6 : 00000000  r5 : 02f9ffa0  r4 : e3710000
  r3 : 000fdffe  r2 : c1e0ce80  r1 : ebf979a0  r0 : 00000000
  Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
  Control: 30c5383d  Table: 235c2a80  DAC: fffffffd
  Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6)
  Stack: (0xe376bbe0 to 0xe376c000)

As it turns out, zsram needs to know the maximum memory size, which
is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in
MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture.

The same problem will be hit on all 32-bit architectures that have a
physical address space larger than 4GB and happen to not enable sparsemem
and include asm/sparsemem.h from asm/pgtable.h.

After the initial discussion, I suggested just always defining
MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is
set, or provoking a build error otherwise. This addresses all
configurations that can currently have this runtime bug, but
leaves all other configurations unchanged.

I looked up the possible number of bits in source code and
datasheets, here is what I found:

 - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used
 - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never
   support more than 32 bits, even though supersections in theory allow
   up to 40 bits as well.
 - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5
   XPA supports up to 60 bits in theory, but 40 bits are more than
   anyone will ever ship
 - On PowerPC, there are three different implementations of 36 bit
   addressing, but 32-bit is used without CONFIG_PTE_64BIT
 - On RISC-V, the normal page table format can support 34 bit
   addressing. There is no highmem support on RISC-V, so anything
   above 2GB is unused, but it might be useful to eventually support
   CONFIG_ZRAM for high pages.

Fixes: 61989a80fb ("staging: zsmalloc: zsmalloc memory allocation library")
Fixes: 02390b87a9 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS")
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Tested-by: Stefan Agner <stefan@agner.ch>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-02 08:49:50 +01:00
Cédric Le Goater 45b5f4b1b4 KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page
commit 75b4962026 upstream.

When accessing the ESB page of a source interrupt, the fault handler
will retrieve the page address from the XIVE interrupt 'xive_irq_data'
structure. If the associated KVM XIVE interrupt is not valid, that is
not allocated at the HW level for some reason, the fault handler will
dereference a NULL pointer leading to the oops below :

  WARNING: CPU: 40 PID: 59101 at arch/powerpc/kvm/book3s_xive_native.c:259 xive_native_esb_fault+0xe4/0x240 [kvm]
  CPU: 40 PID: 59101 Comm: qemu-system-ppc Kdump: loaded Tainted: G        W        --------- -  - 4.18.0-240.el8.ppc64le #1
  NIP:  c00800000e949fac LR: c00000000044b164 CTR: c00800000e949ec8
  REGS: c000001f69617840 TRAP: 0700   Tainted: G        W        --------- -  -  (4.18.0-240.el8.ppc64le)
  MSR:  9000000000029033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 44044282  XER: 00000000
  CFAR: c00000000044b160 IRQMASK: 0
  GPR00: c00000000044b164 c000001f69617ac0 c00800000e96e000 c000001f69617c10
  GPR04: 05faa2b21e000080 0000000000000000 0000000000000005 ffffffffffffffff
  GPR08: 0000000000000000 0000000000000001 0000000000000000 0000000000000001
  GPR12: c00800000e949ec8 c000001ffffd3400 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 c000001f5c065160 c000000001c76f90
  GPR24: c000001f06f20000 c000001f5c065100 0000000000000008 c000001f0eb98c78
  GPR28: c000001dcab40000 c000001dcab403d8 c000001f69617c10 0000000000000011
  NIP [c00800000e949fac] xive_native_esb_fault+0xe4/0x240 [kvm]
  LR [c00000000044b164] __do_fault+0x64/0x220
  Call Trace:
  [c000001f69617ac0] [0000000137a5dc20] 0x137a5dc20 (unreliable)
  [c000001f69617b50] [c00000000044b164] __do_fault+0x64/0x220
  [c000001f69617b90] [c000000000453838] do_fault+0x218/0x930
  [c000001f69617bf0] [c000000000456f50] __handle_mm_fault+0x350/0xdf0
  [c000001f69617cd0] [c000000000457b1c] handle_mm_fault+0x12c/0x310
  [c000001f69617d10] [c00000000007ef44] __do_page_fault+0x264/0xbb0
  [c000001f69617df0] [c00000000007f8c8] do_page_fault+0x38/0xd0
  [c000001f69617e30] [c00000000000a714] handle_page_fault+0x18/0x38
  Instruction dump:
  40c2fff0 7c2004ac 2fa90000 409e0118 73e90001 41820080 e8bd0008 7c2004ac
  7ca90074 39400000 915c0000 7929d182 <0b090000> 2fa50000 419e0080 e89e0018
  ---[ end trace 66c6ff034c53f64f ]---
  xive-kvm: xive_native_esb_fault: accessing invalid ESB page for source 8 !

Fix that by checking the validity of the KVM XIVE interrupt structure.

Fixes: 6520ca64cd ("KVM: PPC: Book3S HV: XIVE: Add a mapping for the source ESB pages")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201105134713.656160-1-clg@kaod.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-02 08:49:46 +01:00
Christophe Leroy 8cad37eb12 powerpc/8xx: Always fault when _PAGE_ACCESSED is not set
commit 29daf869cb upstream.

The kernel expects pte_young() to work regardless of CONFIG_SWAP.

Make sure a minor fault is taken to set _PAGE_ACCESSED when it
is not already set, regardless of the selection of CONFIG_SWAP.

This adds at least 3 instructions to the TLB miss exception
handlers fast path. Following patch will reduce this overhead.

Also update the rotation instruction to the correct number of bits
to reflect all changes done to _PAGE_ACCESSED over time.

Fixes: d069cb4373 ("powerpc/8xx: Don't touch ACCESSED when no SWAP.")
Fixes: 5f356497c3 ("powerpc/8xx: remove unused _PAGE_WRITETHRU")
Fixes: e0a8e0d90a ("powerpc/8xx: Handle PAGE_USER via APG bits")
Fixes: 5b2753fc3e ("powerpc/8xx: Implementation of PAGE_EXEC")
Fixes: a891c43b97 ("powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/af834e8a0f1fa97bfae65664950f0984a70c4750.1602492856.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22 10:14:12 +01:00
Daniel Axtens 01474e8cc3 selftests/powerpc: entry flush test
commit 89a83a0c69 upstream.

Add a test modelled on the RFI flush test which counts the number
of L1D misses doing a simple syscall with the entry flush on and off.

For simplicity of backporting, this test duplicates a lot of code from
the upstream rfi_flush. This is cleaned up upstream, but we don't clean
it up here because it would involve bringing in even more commits.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22 10:14:11 +01:00
Michael Ellerman eb37345ed2 powerpc: Only include kup-radix.h for 64-bit Book3S
commit 178d52c6e8 upstream.

In kup.h we currently include kup-radix.h for all 64-bit builds, which
includes Book3S and Book3E. The latter doesn't make sense, Book3E
never uses the Radix MMU.

This has worked up until now, but almost by accident, and the recent
uaccess flush changes introduced a build breakage on Book3E because of
the bad structure of the code.

So disentangle things so that we only use kup-radix.h for Book3S. This
requires some more stubs in kup.h.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22 10:14:11 +01:00