Commit Graph

767231 Commits

Author SHA1 Message Date
Ram Pai 07f522d203 powerpc/pkeys: make protection key 0 less special
Applications need the ability to associate an address-range with some
key and latter revert to its initial default key. Pkey-0 comes close to
providing this function but falls short, because the current
implementation disallows applications to explicitly associate pkey-0 to
the address range.

Lets make pkey-0 less special and treat it almost like any other key.
Thus it can be explicitly associated with any address range, and can be
freed. This gives the application more flexibility and power.  The
ability to free pkey-0 must be used responsibily, since pkey-0 is
associated with almost all address-range by default.

Even with this change pkey-0 continues to be slightly more special
from the following point of view.
(a) it is implicitly allocated.
(b) it is the default key assigned to any address-range.
(c) its permissions cannot be modified by userspace.

NOTE: (c) is specific to powerpc only. pkey-0 is associated by default
with all pages including kernel pages, and pkeys are also active in
kernel mode. If any permission is denied on pkey-0, the kernel running
in the context of the application will be unable to operate.

Tested on powerpc.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Drop #define PKEY_0 0 in favour of plain old 0]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:43:24 +10:00
Ram Pai a4fcc877d4 powerpc/pkeys: Preallocate execute-only key
execute-only key is allocated dynamically. This is a problem. When a
thread implicitly creates an execute-only key, and resets the UAMOR
for that key, the UAMOR value does not percolate to all the other
threads. Any other thread may ignorantly change the permissions on the
key. This can cause the key to be not execute-only for that thread.

Preallocate the execute-only key and ensure that no thread can change
the permission of the key, by resetting the corresponding bit in
UAMOR.

Fixes: 5586cf61e1 ("powerpc: introduce execute-only pkey")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:38:42 +10:00
Ram Pai fe6a2804e6 powerpc/pkeys: Fix calculation of total pkeys.
Total number of pkeys calculation is off by 1. Fix it.

Fixes: 4fb158f65a ("powerpc: track allocation status of all pkeys")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:35:09 +10:00
Ram Pai c76662e825 powerpc/pkeys: Save the pkey registers before fork
When a thread forks the contents of AMR, IAMR, UAMOR registers in the
newly forked thread are not inherited.

Save the registers before forking, for content of those
registers to be automatically copied into the new thread.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:34:47 +10:00
Ram Pai 4a4a5e5d2a powerpc/pkeys: key allocation/deallocation must not change pkey registers
Key allocation and deallocation has the side effect of programming the
UAMOR/AMR/IAMR registers. This is wrong, since its the responsibility of
the application and not that of the kernel, to modify the permission on
the key.

Do not modify the pkey registers at key allocation/deallocation.

This patch also fixes a bug where a sys_pkey_free() resets the UAMOR
bits of the key, thus making its permissions unmodifiable from user
space. Later if the same key gets reallocated from a different thread
this thread will no longer be able to change the permissions on the key.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:34:08 +10:00
Ram Pai de113256f8 powerpc/pkeys: Deny read/write/execute by default
Deny all permissions on all keys, with some exceptions. pkey-0 must
allow all permissions, or else everything comes to a screaching halt.
Execute-only key must allow execute permission.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:33:41 +10:00
Ram Pai a57a04c76e powerpc/pkeys: Give all threads control of their key permissions
Currently in a multithreaded application, a key allocated by one
thread is not usable by other threads. By "not usable" we mean that
other threads are unable to change the access permissions for that
key for themselves.

When a new key is allocated in one thread, the corresponding UAMOR
bits for that thread get enabled, however the UAMOR bits for that key
for all other threads remain disabled.

Other threads have no way to set permissions on the key, and the
current default permissions are that read/write is enabled for all
keys, which means the key has no effect for other threads. Although
that may be the desired behaviour in some circumstances, having all
threads able to control their permissions for the key is more
flexible.

The current behaviour also differs from the x86 behaviour, which is
problematic for users.

To fix this, enable the UAMOR bits for all keys, at process
creation (in start_thread(), ie exec time). Since the contents of
UAMOR are inherited at fork, all threads are capable of modifying the
permissions on any key.

This is technically an ABI break on powerpc, but pkey support is fairly
new on powerpc and not widely used, and this brings us into
line with x86.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Tested-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Reword some of the changelog]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:32:33 +10:00
Michael Ellerman dbc3f77c2f selftests/powerpc: Consolidate copy/paste test logic
This logic was shared between multiple tests, but now that we have
removed all but one of them we can just move it into that test.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-20 12:50:52 +10:00
Michael Ellerman 525661ef80 selftests/powerpc: Remove Power9 paste tests
Paste on POWER9 only works to accelerators and not on real memory. So
these tests just generate a SIGILL.

So just delete them.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-20 12:50:52 +10:00
Michael Ellerman 83039f22ba selftests/powerpc: Remove Power9 copy_unaligned test
This is a test of the ISA 3.0 "copy" instruction. That instruction has
an L field, which if set to 1 specifies that "the instruction
identifies the beginning of a move group" (pp 858). That's also
referred to as "copy first" vs "copy".

In ISA 3.0B the copy instruction does not have an L field, and the
corresponding bit in the instruction must be set to 1.

This test is generating a "copy" instruction, not a "copy first", and
so on Power9 (which implements 3.0B), this results in an illegal
instruction.

So just drop the test entirely. We still have copy_first_unaligned to
test the "copy first" behaviour.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-20 12:50:51 +10:00
Murilo Opsfelder Araujo ec9336396a powerpc/prom_init: Remove linux,stdout-package property
This property was added in 2004 and the only use of it, which was
already inside `#if 0`, was removed a month later.

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-20 12:50:51 +10:00
Geoff Levand 48e9184686 powerpc/ps3: Set driver coherent_dma_mask
Set the coherent_dma_mask for the PS3 ehci, ohci, and snd devices.

Silences WARN_ON_ONCE messages emitted by the dma_alloc_attrs() routine.

Reported-by: Fredrik Noring <noring@nocrew.org>
Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-20 12:50:37 +10:00
Vaibhav Jain ef6cb5f1a0 cxl: Fix wrong comparison in cxl_adapter_context_get()
Function atomic_inc_unless_negative() returns a bool to indicate
success/failure. However cxl_adapter_context_get() wrongly compares
the return value against '>=0' which will always be true. The patch
fixes this comparison to '==0' there by also fixing this compile time
warning:

	drivers/misc/cxl/main.c:290 cxl_adapter_context_get()
	warn: 'atomic_inc_unless_negative(&adapter->contexts_num)' is unsigned

Fixes: 70b565bbdb ("cxl: Prevent adapter reset if an active context exists")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 21:58:11 +10:00
Alistair Popple 99c3ce33a0 powerpc/powernv/npu: Add a debugfs setting to change ATSD threshold
The threshold at which it becomes more efficient to coalesce a range
of ATSDs into a single per-PID ATSD is currently not well understood
due to a lack of real-world work loads. This patch adds a debugfs
parameter allowing the threshold to be altered at runtime in order to
aid future development and refinement of the value.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 21:58:10 +10:00
Michael Hanselmann d69ccc00c4 MAINTAINERS: Remove the entry for the orphaned ams driver
I no longer have any hardware with the Apple motion sensor and thus
relinquish maintainership of the driver.

Remove the maintainers entry entirely, meaning the code will now fall
under "LINUX FOR POWER MACINTOSH".

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
[mpe: Drop the entry entirely, munge change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 21:58:10 +10:00
Bharat Bhushan fca7bf946e powerpc/mpic: Pass first free vector number to mpic_setup_error_int()
Update the comment to account for the spurious interrupt number. The
code was already accounting for it, but that was unclear because it
was achieved by mpic_setup_error_int() knowing that the number it was
passed was the last used vector, rather than the first free vector.

So change the meaning of the argument to the first free vector and
update the caller to pass 13, instead of 12, to achieve the same
result.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
[mpe: Rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 21:58:09 +10:00
David Gibson fdf743c5c5 powerpc/hugetlbpage: Rmove unhelpful HUGEPD_*_SHIFT macros
The HUGEPD_*_SHIFT macros are always defined to be PGDIR_SHIFT and
PUD_SHIFT, and have to have those values to work properly.  They once used
to have different values, but that was really only because they were used
to mean different things in different contexts.

6fa50483 "powerpc/mm/hugetlb: initialize the pagetable cache correctly for
hugetlb" removed that double meaning, but left the now useless constants.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 14:38:46 +10:00
Randy Dunlap a8bf9e504a chrp/nvram.c: add MODULE_LICENSE()
Add MODULE_LICENSE() to the chrp nvram.c driver to fix the build
warning message:

WARNING: modpost: missing MODULE_LICENSE() in arch/powerpc/platforms/chrp/nvram.o

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 14:38:46 +10:00
Christophe Leroy 8c8c10b90d powerpc/8xx: fix handling of early NULL pointer dereference
NULL pointers are pointers to user memory space. So user pagetable
has to be set in order to avoid random behaviour in case of NULL
pointer dereference, otherwise we may encounter random memory
access hence Machine Check Exception from TLB Miss handlers.

Set user pagetable as early as possible in order to properly
catch early kernel NULL pointer dereference.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19 14:38:45 +10:00
Michael Ellerman ce57c6610c Merge branch 'topic/ppc-kvm' into next
Merge in some commits we're sharing with the KVM tree.

I manually propagated the change from commit d3d4ffaae4
("powerpc/powernv/ioda2: Reduce upper limit for DMA window size") into
pci-ioda-tce.c.

Conflicts:
        arch/powerpc/include/asm/cputable.h
        arch/powerpc/platforms/powernv/pci-ioda.c
        arch/powerpc/platforms/powernv/pci.h
2018-07-19 14:37:57 +10:00
Alexey Kardashevskiy a68bd1267b powerpc/powernv/ioda: Allocate indirect TCE levels on demand
At the moment we allocate the entire TCE table, twice (hardware part and
userspace translation cache). This normally works as we normally have
contigous memory and the guest will map entire RAM for 64bit DMA.

However if we have sparse RAM (one example is a memory device), then
we will allocate TCEs which will never be used as the guest only maps
actual memory for DMA. If it is a single level TCE table, there is nothing
we can really do but if it a multilevel table, we can skip allocating
TCEs we know we won't need.

This adds ability to allocate only first level, saving memory.

This changes iommu_table::free() to avoid allocating of an extra level;
iommu_table::set() will do this when needed.

This adds @alloc parameter to iommu_table::exchange() to tell the callback
if it can allocate an extra level; the flag is set to "false" for
the realmode KVM handlers of H_PUT_TCE hcalls and the callback returns
H_TOO_HARD.

This still requires the entire table to be counted in mm::locked_vm.

To be conservative, this only does on-demand allocation when
the usespace cache table is requested which is the case of VFIO.

The example math for a system replicating a powernv setup with NVLink2
in a guest:
16GB RAM mapped at 0x0
128GB GPU RAM window (16GB of actual RAM) mapped at 0x244000000000

the table to cover that all with 64K pages takes:
(((0x244000000000 + 0x2000000000) >> 16)*8)>>20 = 4556MB

If we allocate only necessary TCE levels, we will only need:
(((0x400000000 + 0x400000000) >> 16)*8)>>20 = 4MB (plus some for indirect
levels).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:11 +10:00
Alexey Kardashevskiy 9bc98c8a43 powerpc/powernv: Rework TCE level allocation
This moves actual pages allocation to a separate function which is going
to be reused later in on-demand TCE allocation.

While we are at it, remove unnecessary level size round up as the caller
does this already.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:10 +10:00
Alexey Kardashevskiy 090bad39b2 powerpc/powernv: Add indirect levels to it_userspace
We want to support sparse memory and therefore huge chunks of DMA windows
do not need to be mapped. If a DMA window big enough to require 2 or more
indirect levels, and a DMA window is used to map all RAM (which is
a default case for 64bit window), we can actually save some memory by
not allocation TCE for regions which we are not going to map anyway.

The hardware tables alreary support indirect levels but we also keep
host-physical-to-userspace translation array which is allocated by
vmalloc() and is a flat array which might use quite some memory.

This converts it_userspace from vmalloc'ed array to a multi level table.

As the format becomes platform dependend, this replaces the direct access
to it_usespace with a iommu_table_ops::useraddrptr hook which returns
a pointer to the userspace copy of a TCE; future extension will return
NULL if the level was not allocated.

This should not change non-KVM handling of TCE tables and it_userspace
will not be allocated for non-KVM tables.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:10 +10:00
Alexey Kardashevskiy 00a5c58d94 KVM: PPC: Make iommu_table::it_userspace big endian
We are going to reuse multilevel TCE code for the userspace copy of
the TCE table and since it is big endian, let's make the copy big endian
too.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:09 +10:00
Alexey Kardashevskiy 191c22879f powerpc/powernv: Move TCE manupulation code to its own file
Right now we have allocation code in pci-ioda.c and traversing code in
pci.c, let's keep them toghether. However both files are big enough
already so let's move this business to a new file.

While we at it, move the code which links IOMMU table groups to
IOMMU tables as it is not specific to any PNV PHB model.

These puts exported symbols from the new file together.

This fixes several warnings from checkpatch.pl like this:
"WARNING: Prefer 'unsigned int' to bare use of 'unsigned'".

As this is almost cut-n-paste, there should be no behavioral change.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:07 +10:00
Alexey Kardashevskiy da2bb0da73 powerpc/powernv: Remove useless wrapper
This gets rid of a useless wrapper around
pnv_pci_ioda2_table_free_pages().

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:47:02 +10:00
Nicholas Piggin 2bf1071a8d powerpc/64s: Remove POWER9 DD1 support
POWER9 DD1 was never a product. It is no longer supported by upstream
firmware, and it is not effectively supported in Linux due to lack of
testing.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
[mpe: Remove arch_make_huge_pte() entirely]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 11:37:21 +10:00
Daniel Klamt 9c3250a127 powerpc/xive: Replace msleep(x) with msleep(OPAL_BUSY_DELAY_MS)
Replace msleep(x) with with msleep(OPAL_BUSY_DELAY_MS) to document
these sleeps are to wait for opal (firmware).

Signed-off-by: Daniel Klamt <eleon@ele0n.de>
Signed-off-by: Bjoern Noetel <bjoern@br3ak3r.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-12 21:08:10 +10:00
Michael Ellerman 54dbcfc211 powerpc/64s: Report SLB multi-hit rather than parity error
When we take an SLB multi-hit on bare metal, we see both the multi-hit
and parity error bits set in DSISR. The user manuals indicates this is
expected to always happen on Power8, whereas on Power9 it says a
multi-hit will "usually" also cause a parity error.

We decide what to do based on the various error tables in mce_power.c,
and because we process them in order and only report the first, we
currently always report a parity error but not the multi-hit, eg:

  Severe Machine check interrupt [Recovered]
    Initiator: CPU
    Error type: SLB [Parity]
      Effective address: c000000ffffd4300

Although this is correct, it leaves the user wondering why they got a
parity error. It would be clearer instead if we reported the
multi-hit because that is more likely to be simply a software bug,
whereas a true parity error is possibly an indication of a bad core.

We can do that simply by reordering the error tables so that multi-hit
appears before parity. That doesn't affect the error recovery at all,
because we flush the SLB either way.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-12 21:08:10 +10:00
Joel Stanley e11b64b1ef powerpc: Remove Power8 DD1 from cputable
This was added to support an early version of Power8 that did not have
working doorbells. These machines were not publicly available, and all of
the internal users have long since upgraded.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-12 21:08:09 +10:00
Bartosz Golaszewski 1e5d75843f powerpc/dts: Use a correct at24 compatible fallback in ac14xx
Using 'at24' as fallback is now deprecated - use the full
'atmel,<model>' string.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-10 10:58:40 +10:00
Bartosz Golaszewski 6aeb43591f powerpc/dts: Use 'atmel' as at24 manufacturer for kmcent2
Using compatible strings without the <manufacturer> part for at24 is
now deprecated. Use a correct 'atmel,<model>' value.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-10 10:58:36 +10:00
Bartosz Golaszewski 835b706bab powerpc/dts: Use 'atmel' as at24 manufacturer for pdm360ng
Using 'at' as the <manufacturer> part of the compatible string is now
deprecated. Use a correct string: 'atmel,<model>'.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-10 10:58:27 +10:00
Shilpasri G Bhat dcb14337e0 cpufreq: powernv: Remove global pstate ramp-down timer in POWER9
POWER9 does not support global pstate requests for the chip. So remove
the timer logic which slowly ramps down the global pstate in P9
platforms.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[mpe: Drop NULL check before kfree(policy->driver_data)]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-09 18:06:02 +10:00
Aaro Koskinen 26064848ef powerpc: Enable kernel XZ compression option on BOOK3S_32
Enable kernel XZ compression option on BOOK3S_32. Tested on G4
PowerBook.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
[mpe: Use one select under the PPC symbol guarded by if PPC_BOOK3S]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-04 22:41:10 +10:00
Kees Cook 1b80ac6484 powerpc/msi: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
switches from an unchanging variable to a constant expression to
eliminate the VLA generation.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-04 22:41:09 +10:00
Alexey Kardashevskiy 00c376fdd7 powerpc/powernv/ioda2: Add 256M IOMMU page size to the default POWER8 case
The sketchy bypass uses 256M pages so add this page size as well.

This should cause no behavioral change but will be used later.

Fixes: 477afd6ea6 "powerpc/ioda: Use ibm,supported-tce-sizes for IOMMU page size mask"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-04 22:41:09 +10:00
Hari Bathini 8950329c4a powerpc/kdump: Handle crashkernel memory reservation failure
Memory reservation for crashkernel could fail if there are holes around
kdump kernel offset (128M). Fail gracefully in such cases and print an
error message.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: David Gibson <dgibson@redhat.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-04 22:40:24 +10:00
Kees Cook 741c5640a1 powerpc/mpc5200: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
switches to using a stack size large enough for the saved routine and
adds a sanity check making sure the routine doesn't overflow into the
0x600 exception handler.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-03 12:00:54 +10:00
Frederic Barrat d497ebf5fb ocxl: Fix page fault handler in case of fault on dying process
If a process exits without doing proper cleanup, there's a window
where an opencapi device can try to access the memory of the dying
process and may trigger a page fault. That's an expected scenario and
the ocxl driver holds a reference on the mm_struct of the process
until the opencapi device is notified of the process exiting.
However, if mm_users is already at 0, i.e. the address space of the
process has already been destroyed, the driver shouldn't try resolving
the page fault, as it will fail, but it can also try accessing already
freed data.

It is fixed by only calling the bottom half of the page fault handler
if mm_users is greater than 0 and get a reference on mm_users instead
of mm_count. Otherwise, we can safely return a translation fault to
the device, as its associated memory context is being removed. The
opencapi device will be properly cleaned up shortly after when closing
the file descriptors.

Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-By: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:59:45 +10:00
Breno Leitao 24bf6864e8 selftests/powerpc: Fix typos
Fix two typos in the file header. Replacing the word 'priviledged'
by 'privileged' and 'exuecuted' by 'executed'.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:59:44 +10:00
Breno Leitao 09a61e894a selftests/powerpc: Fix strncpy usage
There is a buffer overflow in dscr_inherit_test.c test. In main(), strncpy()'s
third argument is the length of the source, not the size of the destination
buffer, which makes strncpy() behaves like strcpy(), causing a buffer overflow
if argv[0] is bigger than LEN_MAX (100).

This patch maps 'prog' to the argv[0] memory region, removing the static
allocation and the LEN_MAX size restriction.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:59:39 +10:00
Frederic Barrat f3988ca4c7 cxl: Remove abandonned capi support for the Mellanox CX4, final cleanup
Remove a few XSL/CX4 oddities which are no longer needed. A simple
revert of the initial commits was not possible (or not worth it) due
to the history of the code.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:33 +10:00
Frederic Barrat f18a4e1d97 Revert "cxl: Allow a default context to be associated with an external pci_dev"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit a19bd79e31.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:33 +10:00
Frederic Barrat 322dc4af6c Revert "cxl: Add cxl_slot_is_supported API"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit 4e56f858bd.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:32 +10:00
Alastair D'Silva 8bf6b91a51 Revert "powerpc/powernv: Add support for the cxl kernel api on the real phb"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit 4361b03430.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:32 +10:00
Alastair D'Silva c8d43cf08a Revert "cxl: Add support for using the kernel API with a real PHB"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit 317f5ef1b3.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:32 +10:00
Alastair D'Silva 29fea8aa21 Revert "cxl: Add cxl_check_and_switch_mode() API to switch bi-modal cards"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit b0b5e5918a.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:31 +10:00
Alastair D'Silva 82c6ae67fb Revert "cxl: Add kernel APIs to get & set the max irqs per context"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit 79384e4b71.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:31 +10:00
Alastair D'Silva 17d2903938 Revert "cxl: Add preliminary workaround for CX4 interrupt limitation"
Remove abandonned capi support for the Mellanox CX4.

This reverts commit cbce0917e2.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:31 +10:00