Commit Graph

881034 Commits

Author SHA1 Message Date
Liang Chen 52d322f919 kthread: Do not preempt current task if it is going to call schedule()
commit 26c7295be0 upstream.

when we create a kthread with ktrhead_create_on_cpu(),the child thread
entry is ktread.c:ktrhead() which will be preempted by the parent after
call complete(done) while schedule() is not called yet,then the parent
will call wait_task_inactive(child) but the child is still on the runqueue,
so the parent will schedule_hrtimeout() for 1 jiffy,it will waste a lot of
time,especially on startup.

  parent                             child
ktrhead_create_on_cpu()
  wait_fo_completion(&done) -----> ktread.c:ktrhead()
                             |----- complete(done);--wakeup and preempted by parent
 kthread_bind() <------------|  |-> schedule();--dequeue here
  wait_task_inactive(child)     |
   schedule_hrtimeout(1 jiffy) -|

So we hope the child just wakeup parent but not preempted by parent, and the
child is going to call schedule() soon,then the parent will not call
schedule_hrtimeout(1 jiffy) as the child is already dequeue.

The same issue for ktrhead_park()&&kthread_parkme().
This patch can save 120ms on rk312x startup with CONFIG_HZ=300.

Signed-off-by: Liang Chen <cl@rock-chips.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200306070133.18335-2-cl@rock-chips.com
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:53 +02:00
Krunoslav Kovac 504fe0ab24 drm/amd/display: fix pow() crashing when given base 0
commit d2e59d0ff4 upstream.

[Why&How]
pow(a,x) is implemented as exp(x*log(a)). log(0) will crash.
So return 0^x = 0, unless x=0, convention seems to be 0^0 = 1.

Cc: stable@vger.kernel.org
Signed-off-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:53 +02:00
Stylon Wang 1f3cfa9338 drm/amd/display: Fix EDID parsing after resume from suspend
commit b24bdc37d0 upstream.

[Why]
Resuming from suspend, CEA blocks from EDID are not parsed and no video
modes can support YUV420. When this happens, output bpc cannot go over
8-bit with 4K modes on HDMI.

[How]
In amdgpu_dm_update_connector_after_detect(), drm_add_edid_modes() is
called after drm_connector_update_edid_property() to fully parse EDID
and update display info.

Cc: stable@vger.kernel.org
Signed-off-by: Stylon Wang <stylon.wang@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:53 +02:00
Daniel Kolesa 6f3bff30f1 drm/amdgpu/display: use GFP_ATOMIC in dcn20_validate_bandwidth_internal
commit f41ed88cbd upstream.

GFP_KERNEL may and will sleep, and this is being executed in
a non-preemptible context; this will mess things up since it's
called inbetween DC_FP_START/END, and rescheduling will result
in the DC_FP_END later being called in a different context (or
just crashing if any floating point/vector registers/instructions
are used after the call is resumed in a different context).

Signed-off-by: Daniel Kolesa <daniel@octaforge.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:52 +02:00
Steffen Maier f45ab6e7d9 scsi: zfcp: Fix use-after-free in request timeout handlers
commit 2d9a2c5f58 upstream.

Before v4.15 commit 75492a5156 ("s390/scsi: Convert timers to use
timer_setup()"), we intentionally only passed zfcp_adapter as context
argument to zfcp_fsf_request_timeout_handler(). Since we only trigger
adapter recovery, it was unnecessary to sync against races between timeout
and (late) completion.  Likewise, we only passed zfcp_erp_action as context
argument to zfcp_erp_timeout_handler(). Since we only wakeup an ERP action,
it was unnecessary to sync against races between timeout and (late)
completion.

Meanwhile the timeout handlers get timer_list as context argument and do a
timer-specific container-of to zfcp_fsf_req which can have been freed.

Fix it by making sure that any request timeout handlers, that might just
have started before del_timer(), are completed by using del_timer_sync()
instead. This ensures the request free happens afterwards.

Space time diagram of potential use-after-free:

Basic idea is to have 2 or more pending requests whose timeouts run out at
almost the same time.

req 1 timeout     ERP thread        req 2 timeout
----------------  ----------------  ---------------------------------------
zfcp_fsf_request_timeout_handler
fsf_req = from_timer(fsf_req, t, timer)
adapter = fsf_req->adapter
zfcp_qdio_siosl(adapter)
zfcp_erp_adapter_reopen(adapter,...)
                  zfcp_erp_strategy
                  ...
                  zfcp_fsf_req_dismiss_all
                  list_for_each_entry_safe
                    zfcp_fsf_req_complete 1
                    del_timer 1
                    zfcp_fsf_req_free 1
                    zfcp_fsf_req_complete 2
                                    zfcp_fsf_request_timeout_handler
                    del_timer 2
                                    fsf_req = from_timer(fsf_req, t, timer)
                    zfcp_fsf_req_free 2
                                    adapter = fsf_req->adapter
                                              ^^^^^^^ already freed

Link: https://lore.kernel.org/r/20200813152856.50088-1-maier@linux.ibm.com
Fixes: 75492a5156 ("s390/scsi: Convert timers to use timer_setup()")
Cc: <stable@vger.kernel.org> #4.15+
Suggested-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:52 +02:00
zhangyi (F) b4062a49ad jbd2: add the missing unlock_buffer() in the error path of jbd2_write_superblock()
commit ef3f5830b8 upstream.

jbd2_write_superblock() is under the buffer lock of journal superblock
before ending that superblock write, so add a missing unlock_buffer() in
in the error path before submitting buffer.

Fixes: 742b06b562 ("jbd2: check superblock mapped prior to committing")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20200620061948.2049579-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:52 +02:00
Jan Kara 2bc54ba65f ext4: fix checking of directory entry validity for inline directories
commit 7303cb5bfe upstream.

ext4_search_dir() and ext4_generic_delete_entry() can be called both for
standard director blocks and for inline directories stored inside inode
or inline xattr space. For the second case we didn't call
ext4_check_dir_entry() with proper constraints that could result in
accepting corrupted directory entry as well as false positive filesystem
errors like:

EXT4-fs error (device dm-0): ext4_search_dir:1395: inode #28320400:
block 113246792: comm dockerd: bad entry in directory: directory entry too
close to block end - offset=0, inode=28320403, rec_len=32, name_len=8,
size=4096

Fix the arguments passed to ext4_check_dir_entry().

Fixes: 109ba779d6 ("ext4: check for directory entries too close to block end")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200731162135.8080-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:52 +02:00
Kaike Wan 59af0759bd RDMA/hfi1: Correct an interlock issue for TID RDMA WRITE request
commit b25e8e85e7 upstream.

The following message occurs when running an AI application with TID RDMA
enabled:

hfi1 0000:7f:00.0: hfi1_0: [QP74] hfi1_tid_timeout 4084
hfi1 0000:7f:00.0: hfi1_0: [QP70] hfi1_tid_timeout 4084

The issue happens when TID RDMA WRITE request is followed by an
IB_WR_RDMA_WRITE_WITH_IMM request, the latter could be completed first on
the responder side. As a result, no ACK packet for the latter could be
sent because the TID RDMA WRITE request is still being processed on the
responder side.

When the TID RDMA WRITE request is eventually completed, the requester
will wait for the IB_WR_RDMA_WRITE_WITH_IMM request to be acknowledged.

If the next request is another TID RDMA WRITE request, no TID RDMA WRITE
DATA packet could be sent because the preceding IB_WR_RDMA_WRITE_WITH_IMM
request is not completed yet.

Consequently the IB_WR_RDMA_WRITE_WITH_IMM will be retried but it will be
ignored on the responder side because the responder thinks it has already
been completed. Eventually the retry will be exhausted and the qp will be
put into error state on the requester side. On the responder side, the TID
resource timer will eventually expire because no TID RDMA WRITE DATA
packets will be received for the second TID RDMA WRITE request.  There is
also risk of a write-after-write memory corruption due to the issue.

Fix by adding a requester side interlock to prevent any potential data
corruption and TID RDMA protocol error.

Fixes: a0b34f75ec ("IB/hfi1: Add interlock between a TID RDMA request and other requests")
Link: https://lore.kernel.org/r/20200811174931.191210.84093.stgit@awfm-01.aw.intel.com
Cc: <stable@vger.kernel.org> # 5.4.x+
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:52 +02:00
Charan Teja Reddy 0cfb9320d0 mm, page_alloc: fix core hung in free_pcppages_bulk()
commit 88e8ac11d2 upstream.

The following race is observed with the repeated online, offline and a
delay between two successive online of memory blocks of movable zone.

P1						P2

Online the first memory block in
the movable zone. The pcp struct
values are initialized to default
values,i.e., pcp->high = 0 &
pcp->batch = 1.

					Allocate the pages from the
					movable zone.

Try to Online the second memory
block in the movable zone thus it
entered the online_pages() but yet
to call zone_pcp_update().
					This process is entered into
					the exit path thus it tries
					to release the order-0 pages
					to pcp lists through
					free_unref_page_commit().
					As pcp->high = 0, pcp->count = 1
					proceed to call the function
					free_pcppages_bulk().
Update the pcp values thus the
new pcp values are like, say,
pcp->high = 378, pcp->batch = 63.
					Read the pcp's batch value using
					READ_ONCE() and pass the same to
					free_pcppages_bulk(), pcp values
					passed here are, batch = 63,
					count = 1.

					Since num of pages in the pcp
					lists are less than ->batch,
					then it will stuck in
					while(list_empty(list)) loop
					with interrupts disabled thus
					a core hung.

Avoid this by ensuring free_pcppages_bulk() is called with proper count of
pcp list pages.

The mentioned race is some what easily reproducible without [1] because
pcp's are not updated for the first memory block online and thus there is
a enough race window for P2 between alloc+free and pcp struct values
update through onlining of second memory block.

With [1], the race still exists but it is very narrow as we update the pcp
struct values for the first memory block online itself.

This is not limited to the movable zone, it could also happen in cases
with the normal zone (e.g., hotplug to a node that only has DMA memory, or
no other memory yet).

[1]: https://patchwork.kernel.org/patch/11696389/

Fixes: 5f8dcc2121 ("page-allocator: split per-cpu list into one-list-per-migrate-type")
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: <stable@vger.kernel.org> [2.6+]
Link: http://lkml.kernel.org/r/1597150703-19003-1-git-send-email-charante@codeaurora.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:51 +02:00
Doug Berger 5663159e29 mm: include CMA pages in lowmem_reserve at boot
commit e08d3fdfe2 upstream.

The lowmem_reserve arrays provide a means of applying pressure against
allocations from lower zones that were targeted at higher zones.  Its
values are a function of the number of pages managed by higher zones and
are assigned by a call to the setup_per_zone_lowmem_reserve() function.

The function is initially called at boot time by the function
init_per_zone_wmark_min() and may be called later by accesses of the
/proc/sys/vm/lowmem_reserve_ratio sysctl file.

The function init_per_zone_wmark_min() was moved up from a module_init to
a core_initcall to resolve a sequencing issue with khugepaged.
Unfortunately this created a sequencing issue with CMA page accounting.

The CMA pages are added to the managed page count of a zone when
cma_init_reserved_areas() is called at boot also as a core_initcall.  This
makes it uncertain whether the CMA pages will be added to the managed page
counts of their zones before or after the call to
init_per_zone_wmark_min() as it becomes dependent on link order.  With the
current link order the pages are added to the managed count after the
lowmem_reserve arrays are initialized at boot.

This means the lowmem_reserve values at boot may be lower than the values
used later if /proc/sys/vm/lowmem_reserve_ratio is accessed even if the
ratio values are unchanged.

In many cases the difference is not significant, but for example
an ARM platform with 1GB of memory and the following memory layout

  cma: Reserved 256 MiB at 0x0000000030000000
  Zone ranges:
    DMA      [mem 0x0000000000000000-0x000000002fffffff]
    Normal   empty
    HighMem  [mem 0x0000000030000000-0x000000003fffffff]

would result in 0 lowmem_reserve for the DMA zone.  This would allow
userspace to deplete the DMA zone easily.

Funnily enough

  $ cat /proc/sys/vm/lowmem_reserve_ratio

would fix up the situation because as a side effect it forces
setup_per_zone_lowmem_reserve.

This commit breaks the link order dependency by invoking
init_per_zone_wmark_min() as a postcore_initcall so that the CMA pages
have the chance to be properly accounted in their zone(s) and allowing
the lowmem_reserve arrays to receive consistent values.

Fixes: bc22af74f2 ("mm: update min_free_kbytes from khugepaged after core initialization")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1597423766-27849-1-git-send-email-opendmb@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:51 +02:00
Hugh Dickins e9e3ec03e6 uprobes: __replace_page() avoid BUG in munlock_vma_page()
commit c17c3dc9d0 upstream.

syzbot crashed on the VM_BUG_ON_PAGE(PageTail) in munlock_vma_page(), when
called from uprobes __replace_page().  Which of many ways to fix it?
Settled on not calling when PageCompound (since Head and Tail are equals
in this context, PageCompound the usual check in uprobes.c, and the prior
use of FOLL_SPLIT_PMD will have cleared PageMlocked already).

Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>	[5.4+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008161338360.20413@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:51 +02:00
Wei Yongjun fa2e0d4e4a kernel/relay.c: fix memleak on destroy relay channel
commit 71e843295c upstream.

kmemleak report memory leak as follows:

  unreferenced object 0x607ee4e5f948 (size 8):
  comm "syz-executor.1", pid 2098, jiffies 4295031601 (age 288.468s)
  hex dump (first 8 bytes):
  00 00 00 00 00 00 00 00 ........
  backtrace:
     relay_open kernel/relay.c:583 [inline]
     relay_open+0xb6/0x970 kernel/relay.c:563
     do_blk_trace_setup+0x4a8/0xb20 kernel/trace/blktrace.c:557
     __blk_trace_setup+0xb6/0x150 kernel/trace/blktrace.c:597
     blk_trace_ioctl+0x146/0x280 kernel/trace/blktrace.c:738
     blkdev_ioctl+0xb2/0x6a0 block/ioctl.c:613
     block_ioctl+0xe5/0x120 fs/block_dev.c:1871
     vfs_ioctl fs/ioctl.c:48 [inline]
     __do_sys_ioctl fs/ioctl.c:753 [inline]
     __se_sys_ioctl fs/ioctl.c:739 [inline]
     __x64_sys_ioctl+0x170/0x1ce fs/ioctl.c:739
     do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

'chan->buf' is malloced in relay_open() by alloc_percpu() but not free
while destroy the relay channel.  Fix it by adding free_percpu() before
return from relay_destroy_channel().

Fixes: 017c59c042 ("relay: Use per CPU constructs for the relay channel buffer pointers")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Akash Goel <akash.goel@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200817122826.48518-1-weiyongjun1@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:51 +02:00
Jann Horn 19a77c937a romfs: fix uninitialized memory leak in romfs_dev_read()
commit bcf85fcedf upstream.

romfs has a superblock field that limits the size of the filesystem; data
beyond that limit is never accessed.

romfs_dev_read() fetches a caller-supplied number of bytes from the
backing device.  It returns 0 on success or an error code on failure;
therefore, its API can't represent short reads, it's all-or-nothing.

However, when romfs_dev_read() detects that the requested operation would
cross the filesystem size limit, it currently silently truncates the
requested number of bytes.  This e.g.  means that when the content of a
file with size 0x1000 starts one byte before the filesystem size limit,
->readpage() will only fill a single byte of the supplied page while
leaving the rest uninitialized, leaking that uninitialized memory to
userspace.

Fix it by returning an error code instead of truncating the read when the
requested read operation would go beyond the end of the filesystem.

Fixes: da4458bda2 ("NOMMU: Make it possible for RomFS to use MTD devices directly")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200818013202.2246365-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:51 +02:00
Lukas Wunner 3e538c536f spi: Prevent adding devices below an unregistering controller
commit ddf75be47c upstream.

CONFIG_OF_DYNAMIC and CONFIG_ACPI allow adding SPI devices at runtime
using a DeviceTree overlay or DSDT patch.  CONFIG_SPI_SLAVE allows the
same via sysfs.

But there are no precautions to prevent adding a device below a
controller that's being removed.  Such a device is unusable and may not
even be able to unbind cleanly as it becomes inaccessible once the
controller has been torn down.  E.g. it is then impossible to quiesce
the device's interrupt.

of_spi_notify() and acpi_spi_notify() do hold a ref on the controller,
but otherwise run lockless against spi_unregister_controller().

Fix by holding the spi_add_lock in spi_unregister_controller() and
bailing out of spi_add_device() if the controller has been unregistered
concurrently.

Fixes: ce79d54ae4 ("spi/of: Add OF notifier handler")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.19+
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Octavian Purdila <octavian.purdila@intel.com>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Link: https://lore.kernel.org/r/a8c3205088a969dc8410eec1eba9aface60f36af.1596451035.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:50 +02:00
Oleksij Rempel 143df6b358 can: j1939: socket: j1939_sk_bind(): make sure ml_priv is allocated
commit af804b7826 upstream.

This patch adds check to ensure that the struct net_device::ml_priv is
allocated, as it is used later by the j1939 stack.

The allocation is done by all mainline CAN network drivers, but when using
bond or team devices this is not the case.

Bail out if no ml_priv is allocated.

Reported-by: syzbot+f03d384f3455d28833eb@syzkaller.appspotmail.com
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Cc: linux-stable <stable@vger.kernel.org> # >= v5.4
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20200807105200.26441-4-o.rempel@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:50 +02:00
Oleksij Rempel 60be1488a3 can: j1939: transport: j1939_session_tx_dat(): fix use-after-free read in j1939_tp_txtimer()
commit cd3b3636c9 upstream.

The current stack implementation do not support ECTS requests of not
aligned TP sized blocks.

If ECTS will request a block with size and offset spanning two TP
blocks, this will cause memcpy() to read beyond the queued skb (which
does only contain one TP sized block).

Sometimes KASAN will detect this read if the memory region beyond the
skb was previously allocated and freed. In other situations it will stay
undetected. The ETP transfer in any case will be corrupted.

This patch adds a sanity check to avoid this kind of read and abort the
session with error J1939_XTP_ABORT_ECTS_TOO_BIG.

Reported-by: syzbot+5322482fe520b02aea30@syzkaller.appspotmail.com
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Cc: linux-stable <stable@vger.kernel.org> # >= v5.4
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20200807105200.26441-3-o.rempel@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:50 +02:00
Mike Pozulp 055c65c7e7 ALSA: hda/realtek: Add quirk for Samsung Galaxy Book Ion
commit e17f02d055 upstream.

The Galaxy Book Ion uses the same ALC298 codec as other Samsung laptops
which have the no headphone sound bug, like my Samsung Notebook. The
Galaxy Book owner confirmed that this patch fixes the bug.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207423
Signed-off-by: Mike Pozulp <pozulp.kernel@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200818165446.499821-1-pozulp.kernel@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:50 +02:00
Mike Pozulp 4fe52a85ee ALSA: hda/realtek: Add quirk for Samsung Galaxy Flex Book
commit f70fff83cd upstream.

The Flex Book uses the same ALC298 codec as other Samsung laptops which
have the no headphone sound bug, like my Samsung Notebook. The Flex Book
owner used Early Patching to confirm that this quirk fixes the bug.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207423
Signed-off-by: Mike Pozulp <pozulp.kernel@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200814045346.645367-1-pozulp.kernel@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:50 +02:00
David Sterba 84bfb4b10d btrfs: add wrapper for transaction abort predicate
[ Upstream commit bf31f87f71 ]

The status of aborted transaction can change between calls and it needs
to be accessed by READ_ONCE. Add a helper that also wraps the unlikely
hint.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:49 +02:00
Josef Bacik 745148367b btrfs: return EROFS for BTRFS_FS_STATE_ERROR cases
Eric reported seeing this message while running generic/475

  BTRFS: error (device dm-3) in btrfs_sync_log:3084: errno=-117 Filesystem corrupted

Full stack trace:

  BTRFS: error (device dm-0) in btrfs_commit_transaction:2323: errno=-5 IO failure (Error while writing out transaction)
  BTRFS info (device dm-0): forced readonly
  BTRFS warning (device dm-0): Skipping commit of aborted transaction.
  ------------[ cut here ]------------
  BTRFS: error (device dm-0) in cleanup_transaction:1894: errno=-5 IO failure
  BTRFS: Transaction aborted (error -117)
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6480 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6488 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6490 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c6498 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64a0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64a8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64b0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64b8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3555 rw 0,0 sector 0x1c64c0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3572 rw 0,0 sector 0x1b85e8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3572 rw 0,0 sector 0x1b85f0 len 4096 err no 10
  WARNING: CPU: 3 PID: 23985 at fs/btrfs/tree-log.c:3084 btrfs_sync_log+0xbc8/0xd60 [btrfs]
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4288 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4290 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d4298 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42a0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42a8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42b0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42b8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42c0 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42c8 len 4096 err no 10
  BTRFS warning (device dm-0): direct IO failed ino 3548 rw 0,0 sector 0x1d42d0 len 4096 err no 10
  CPU: 3 PID: 23985 Comm: fsstress Tainted: G        W    L    5.8.0-rc4-default+ #1181
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
  RIP: 0010:btrfs_sync_log+0xbc8/0xd60 [btrfs]
  RSP: 0018:ffff909a44d17bd0 EFLAGS: 00010286
  RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
  RDX: ffff8f3be41cb940 RSI: ffffffffb0108d2b RDI: ffffffffb0108ff7
  RBP: ffff909a44d17e70 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000037988 R12: ffff8f3bd20e4000
  R13: ffff8f3bd20e4428 R14: 00000000ffffff8b R15: ffff909a44d17c70
  FS:  00007f6a6ed3fb80(0000) GS:ffff8f3c3dc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f6a6ed3e000 CR3: 00000000525c0003 CR4: 0000000000160ee0
  Call Trace:
   ? finish_wait+0x90/0x90
   ? __mutex_unlock_slowpath+0x45/0x2a0
   ? lock_acquire+0xa3/0x440
   ? lockref_put_or_lock+0x9/0x30
   ? dput+0x20/0x4a0
   ? dput+0x20/0x4a0
   ? do_raw_spin_unlock+0x4b/0xc0
   ? _raw_spin_unlock+0x1f/0x30
   btrfs_sync_file+0x335/0x490 [btrfs]
   do_fsync+0x38/0x70
   __x64_sys_fsync+0x10/0x20
   do_syscall_64+0x50/0xe0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f6a6ef1b6e3
  Code: Bad RIP value.
  RSP: 002b:00007ffd01e20038 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
  RAX: ffffffffffffffda RBX: 000000000007a120 RCX: 00007f6a6ef1b6e3
  RDX: 00007ffd01e1ffa0 RSI: 00007ffd01e1ffa0 RDI: 0000000000000003
  RBP: 0000000000000003 R08: 0000000000000001 R09: 00007ffd01e2004c
  R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000009f
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
  irq event stamp: 0
  hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  hardirqs last disabled at (0): [<ffffffffb007fe0b>] copy_process+0x67b/0x1b00
  softirqs last  enabled at (0): [<ffffffffb007fe0b>] copy_process+0x67b/0x1b00
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  ---[ end trace af146e0e38433456 ]---
  BTRFS: error (device dm-0) in btrfs_sync_log:3084: errno=-117 Filesystem corrupted

This ret came from btrfs_write_marked_extents().  If we get an aborted
transaction via EIO before, we'll see it in btree_write_cache_pages()
and return EUCLEAN, which gets printed as "Filesystem corrupted".

Except we shouldn't be returning EUCLEAN here, we need to be returning
EROFS because EUCLEAN is reserved for actual corruption, not IO errors.

We are inconsistent about our handling of BTRFS_FS_STATE_ERROR
elsewhere, but we want to use EROFS for this particular case.  The
original transaction abort has the real error code for why we ended up
with an aborted transaction, all subsequent actions just need to return
EROFS because they may not have a trans handle and have no idea about
the original cause of the abort.

After patch "btrfs: don't WARN if we abort a transaction with EROFS" the
stacktrace will not be dumped either.

Reported-by: Eric Sandeen <esandeen@redhat.com>
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add full test stacktrace ]
Signed-off-by: David Sterba <dsterba@suse.com>
2020-08-26 10:40:49 +02:00
Josef Bacik de88b7e2f0 btrfs: don't show full path of bind mounts in subvol=
[ Upstream commit 3ef3959b29 ]

Chris Murphy reported a problem where rpm ostree will bind mount a bunch
of things for whatever voodoo it's doing.  But when it does this
/proc/mounts shows something like

  /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0
  /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo/bar 0 0

Despite subvolid=256 being subvol=/foo.  This is because we're just
spitting out the dentry of the mount point, which in the case of bind
mounts is the source path for the mountpoint.  Instead we should spit
out the path to the actual subvol.  Fix this by looking up the name for
the subvolid we have mounted.  With this fix the same test looks like
this

  /dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0
  /dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo 0 0

Reported-by: Chris Murphy <chris@colorremedies.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:49 +02:00
Marcos Paulo de Souza 038580b1f5 btrfs: export helpers for subvolume name/id resolution
[ Upstream commit c0c907a47d ]

The functions will be used outside of export.c and super.c to allow
resolving subvolume name from a given id, eg. for subvolume deletion by
id ioctl.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ split from the next patch ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:49 +02:00
Coly Li b407539849 bcache: avoid nr_stripes overflow in bcache_device_init()
[ Upstream commit 65f0f017e7 ]

For some block devices which large capacity (e.g. 8TB) but small io_opt
size (e.g. 8 sectors), in bcache_device_init() the stripes number calcu-
lated by,
	DIV_ROUND_UP_ULL(sectors, d->stripe_size);
might be overflow to the unsigned int bcache_device->nr_stripes.

This patch uses the uint64_t variable to store DIV_ROUND_UP_ULL()
and after the value is checked to be available in unsigned int range,
sets it to bache_device->nr_stripes. Then the overflow is avoided.

Reported-and-tested-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1783075
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Hugh Dickins 9f4f7c08d5 khugepaged: adjust VM_BUG_ON_MM() in __khugepaged_enter()
[ Upstream commit f3f99d63a8 ]

syzbot crashes on the VM_BUG_ON_MM(khugepaged_test_exit(mm), mm) in
__khugepaged_enter(): yes, when one thread is about to dump core, has set
core_state, and is waiting for others, another might do something calling
__khugepaged_enter(), which now crashes because I lumped the core_state
test (known as "mmget_still_valid") into khugepaged_test_exit().  I still
think it's best to lump them together, so just in this exceptional case,
check mm->mm_users directly instead of khugepaged_test_exit().

Fixes: bbe98f9cad ("khugepaged: khugepaged_test_exit() check mmget_still_valid()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: <stable@vger.kernel.org>	[4.8+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008141503370.18085@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Hugh Dickins 9a05b774af khugepaged: khugepaged_test_exit() check mmget_still_valid()
[ Upstream commit bbe98f9cad ]

Move collapse_huge_page()'s mmget_still_valid() check into
khugepaged_test_exit() itself.  collapse_huge_page() is used for anon THP
only, and earned its mmget_still_valid() check because it inserts a huge
pmd entry in place of the page table's pmd entry; whereas
collapse_file()'s retract_page_tables() or collapse_pte_mapped_thp()
merely clears the page table's pmd entry.  But core dumping without mmap
lock must have been as open to mistaking a racily cleared pmd entry for a
page table at physical page 0, as exit_mmap() was.  And we certainly have
no interest in mapping as a THP once dumping core.

Fixes: 59ea6d06cf ("coredump: fix race condition between collapse_huge_page() and core dumping")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>	[4.8+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008021217020.27773@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Masami Hiramatsu 8043d5ee91 perf probe: Fix memory leakage when the probe point is not found
[ Upstream commit 12d572e785 ]

Fix the memory leakage in debuginfo__find_trace_events() when the probe
point is not found in the debuginfo. If there is no probe point found in
the debuginfo, debuginfo__find_probes() will NOT return -ENOENT, but 0.

Thus the caller of debuginfo__find_probes() must check the tf.ntevs and
release the allocated memory for the array of struct probe_trace_event.

The current code releases the memory only if the debuginfo__find_probes()
hits an error but not checks tf.ntevs. In the result, the memory allocated
on *tevs are not released if tf.ntevs == 0.

This fixes the memory leakage by checking tf.ntevs == 0 in addition to
ret < 0.

Fixes: ff74178350 ("perf probe: Introduce debuginfo to encapsulate dwarf information")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/159438668346.62703.10887420400718492503.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Bob Peterson 888d9b829c gfs2: Never call gfs2_block_zero_range with an open transaction
[ Upstream commit 70499cdfeb ]

Before this patch, some functions started transactions then they called
gfs2_block_zero_range. However, gfs2_block_zero_range, like writes, can
start transactions, which results in a recursive transaction error.
For example:

do_shrink
   trunc_start
      gfs2_trans_begin <------------------------------------------------
         gfs2_block_zero_range
            iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops);
               iomap_apply ... iomap_zero_range_actor
                  iomap_begin
                     gfs2_iomap_begin
                        gfs2_iomap_begin_write
                  actor (iomap_zero_range_actor)
		     iomap_zero
			iomap_write_begin
			   gfs2_iomap_page_prepare
			      gfs2_trans_begin <------------------------

This patch reorders the callers of gfs2_block_zero_range so that they
only start their transactions after the call. It also adds a BUG_ON to
ensure this doesn't happen again.

Fixes: 2257e468a6 ("gfs2: implement gfs2_block_zero_range using iomap_zero_range")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Andreas Gruenbacher 18a640d3b5 gfs2: Improve mmap write vs. punch_hole consistency
[ Upstream commit 39c3a948ec ]

When punching a hole in a file, use filemap_write_and_wait_range to
write back any dirty pages in the range of the hole.  As a side effect,
if the hole isn't page aligned, this marks unaligned pages at the
beginning and the end of the hole read-only.  This is required when the
block size is smaller than the page size: when those pages are written
to again after the hole punching, we must make sure that page_mkwrite is
called for those pages so that the page will be fully allocated and any
blocks turned into holes from the hole punching will be reallocated.
(If a page is writably mapped, page_mkwrite won't be called.)

Fixes xfstest generic/567.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:48 +02:00
Chris Wilson e42c75ef34 drm/vgem: Replace opencoded version of drm_gem_dumb_map_offset()
[ Upstream commit 119c53d2d4 ]

drm_gem_dumb_map_offset() now exists and does everything
vgem_gem_dump_map does and *ought* to do.

In particular, vgem_gem_dumb_map() was trying to reject mmapping an
imported dmabuf by checking the existence of obj->filp. Unfortunately,
we always allocated an obj->filp, even if unused for an imported dmabuf.
Instead, the drm_gem_dumb_map_offset(), since commit 90378e5891
("drm/gem: drm_gem_dumb_map_offset(): reject dma-buf"), uses the
obj->import_attach to reject such invalid mmaps.

This prevents vgem from allowing userspace mmapping the dumb handle and
attempting to incorrectly fault in remote pages belonging to another
device, where there may not even be a struct page.

v2: Use the default drm_gem_dumb_map_offset() callback

Fixes: af33a9190d ("drm/vgem: Enable dmabuf import interfaces")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <stable@vger.kernel.org> # v4.13+
Link: https://patchwork.freedesktop.org/patch/msgid/20200708154911.21236-1-chris@chris-wilson.co.uk
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:47 +02:00
Masahiro Yamada 62353048e2 kbuild: support LLVM=1 to switch the default tools to Clang/LLVM
commit a0d1c951ef upstream.

As Documentation/kbuild/llvm.rst implies, building the kernel with a
full set of LLVM tools gets very verbose and unwieldy.

Provide a single switch LLVM=1 to use Clang and LLVM tools instead
of GCC and Binutils. You can pass it from the command line or as an
environment variable.

Please note LLVM=1 does not turn on the integrated assembler. You need
to pass LLVM_IAS=1 to use it. When the upstream kernel is ready for the
integrated assembler, I think we can make it default.

We discussed what we need, and we agreed to go with a simple boolean
flag that switches both target and host tools:

  https://lkml.org/lkml/2020/3/28/494
  https://lkml.org/lkml/2020/4/3/43

Some items discussed, but not adopted:

- LLVM_DIR

  When multiple versions of LLVM are installed, I just thought supporting
  LLVM_DIR=/path/to/my/llvm/bin/ might be useful.

  CC      = $(LLVM_DIR)clang
  LD      = $(LLVM_DIR)ld.lld
    ...

  However, we can handle this by modifying PATH. So, we decided to not do
  this.

- LLVM_SUFFIX

  Some distributions (e.g. Debian) package specific versions of LLVM with
  naming conventions that use the version as a suffix.

  CC      = clang$(LLVM_SUFFIX)
  LD      = ld.lld(LLVM_SUFFIX)
    ...

  will allow a user to pass LLVM_SUFFIX=-11 to use clang-11 etc.,
  but the suffixed versions in /usr/bin/ are symlinks to binaries in
  /usr/lib/llvm-#/bin/, so this can also be handled by PATH.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com> # build
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:47 +02:00
Masahiro Yamada c7d8f67db1 kbuild: replace AS=clang with LLVM_IAS=1
commit 7e20e47c70 upstream.

The 'AS' variable is unused for building the kernel. Only the remaining
usage is to turn on the integrated assembler. A boolean flag is a better
fit for this purpose.

AS=clang was added for experts. So, I replaced it with LLVM_IAS=1,
breaking the backward compatibility.

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:47 +02:00
Masahiro Yamada 244d902676 kbuild: remove AS variable
commit aa824e0c96 upstream.

As commit 5ef872636c ("kbuild: get rid of misleading $(AS) from
documents") noted, we rarely use $(AS) directly in the kernel build.

Now that the only/last user of $(AS) in drivers/net/wan/Makefile was
converted to $(CC), $(AS) is no longer used in the build process.

You can still pass in AS=clang, which is just a switch to turn on
the LLVM integrated assembler.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:47 +02:00
Masahiro Yamada fed06097ac kbuild: remove PYTHON2 variable
commit 94f7345b71 upstream.

Python 2 has retired. There is no user of this variable.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Dmitry Golovin fa84d9f315 x86/boot: kbuild: allow readelf executable to be specified
commit eefb8c124f upstream.

Introduce a new READELF variable to top-level Makefile, so the name of
readelf binary can be specified.

Before this change the name of the binary was hardcoded to
"$(CROSS_COMPILE)readelf" which might not be present for every
toolchain.

This allows to build with LLVM Object Reader by using make parameter
READELF=llvm-readelf.

Link: https://github.com/ClangBuiltLinux/linux/issues/771
Signed-off-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Masahiro Yamada c173511a12 net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
commit 734f3719d3 upstream.

The firmware source, wanxlfw.S, is currently compiled by the combo of
$(CPP) and $(M68KAS). This is not what we usually do for compiling *.S
files. In fact, this Makefile is the only user of $(AS) in the kernel
build.

Instead of combining $(CPP) and (AS) from different tool sets, using
$(M68KCC) as an assembler driver is simpler, and saner.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Masahiro Yamada c7c239c947 net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
commit 63b903dfeb upstream.

As far as I understood from the Kconfig help text, this build rule is
used to rebuild the driver firmware, which runs on an old m68k-based
chip. So, you need m68k tools for the firmware rebuild.

wanxl.c is a PCI driver, but CONFIG_M68K does not select CONFIG_HAVE_PCI.
So, you cannot enable CONFIG_WANXL_BUILD_FIRMWARE for ARCH=m68k. In other
words, ifeq ($(ARCH),m68k) is false here.

I am keeping the dead code for now, but rebuilding the firmware requires
'as68k' and 'ld68k', which I do not have in hand.

Instead, the kernel.org m68k GCC [1] successfully built it.

Allowing a user to pass in CROSS_COMPILE_M68K= is handier.

[1] https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/9.2.0/x86_64-gcc-9.2.0-nolibc-m68k-linux.tar.xz

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Fangrui Song f781285d09 Documentation/llvm: fix the name of llvm-size
commit 0f44fbc162 upstream.

The tool is called llvm-size, not llvm-objsize.

Fixes: fcf1b6a35c ("Documentation/llvm: add documentation on building w/ Clang/LLVM")
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Nick Desaulniers 97eab9af00 Documentation/llvm: add documentation on building w/ Clang/LLVM
commit fcf1b6a35c upstream.

added to kbuild documentation. Provides more official info on building
kernels with Clang and LLVM than our wiki.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26 10:40:46 +02:00
Greg Kroah-Hartman 77fcb48939 Linux 5.4.60
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
hersen wu 53a856c5a6 drm/amd/display: dchubbub p-state warning during surface planes switch
commit 8b0379a857 upstream.

[Why]
ramp_up_dispclk_with_dpp is to change dispclk, dppclk and dprefclk
according to bandwidth requirement. call stack: rv1_update_clocks -->
update_clocks --> dcn10_prepare_bandwidth / dcn10_optimize_bandwidth
--> prepare_bandwidth / optimize_bandwidth. before change dcn hw,
prepare_bandwidth will be called first to allow enough clock,
watermark for change, after end of dcn hw change, optimize_bandwidth
is executed to lower clock to save power for new dcn hw settings.

below is sequence of commit_planes_for_stream:
step 1: prepare_bandwidth - raise clock to have enough bandwidth
step 2: lock_doublebuffer_enable
step 3: pipe_control_lock(true) - make dchubp register change will
not take effect right way
step 4: apply_ctx_for_surface - program dchubp
step 5: pipe_control_lock(false) - dchubp register change take effect
step 6: optimize_bandwidth --> dc_post_update_surfaces_to_stream
for full_date, optimize clock to save power

at end of step 1, dcn clocks (dprefclk, dispclk, dppclk) may be
changed for new dchubp configuration. but real dcn hub dchubps are
still running with old configuration until end of step 5. this need
clocks settings at step 1 should not less than that before step 1.
this is checked by two conditions: 1. if (should_set_clock(safe_to_lower
, new_clocks->dispclk_khz, clk_mgr_base->clks.dispclk_khz) ||
new_clocks->dispclk_khz == clk_mgr_base->clks.dispclk_khz)
2. request_dpp_div = new_clocks->dispclk_khz > new_clocks->dppclk_khz

the second condition is based on new dchubp configuration. dppclk
for new dchubp may be different from dppclk before step 1.
for example, before step 1, dchubps are as below:
pipe 0: recout=(0,40,1920,980) viewport=(0,0,1920,979)
pipe 1: recout=(0,0,1920,1080) viewport=(0,0,1920,1080)
for dppclk for pipe0 need dppclk = dispclk

new dchubp pipe split configuration:
pipe 0: recout=(0,0,960,1080) viewport=(0,0,960,1080)
pipe 1: recout=(960,0,960,1080) viewport=(960,0,960,1080)
dppclk only needs dppclk = dispclk /2.

dispclk, dppclk are not lock by otg master lock. they take effect
after step 1. during this transition, dispclk are the same, but
dppclk is changed to half of previous clock for old dchubp
configuration between step 1 and step 6. This may cause p-state
warning intermittently.

[How]
for new_clocks->dispclk_khz == clk_mgr_base->clks.dispclk_khz, we
need make sure dppclk are not changed to less between step 1 and 6.
for new_clocks->dispclk_khz > clk_mgr_base->clks.dispclk_khz,
new display clock is raised, but we do not know ratio of
new_clocks->dispclk_khz and clk_mgr_base->clks.dispclk_khz,
new_clocks->dispclk_khz /2 does not guarantee equal or higher than
old dppclk. we could ignore power saving different between
dppclk = displck and dppclk = dispclk / 2 between step 1 and step 6.
as long as safe_to_lower = false, set dpclk = dispclk to simplify
condition check.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Eryk Brol <eryk.brol@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Sandeep Raghuraman 4287c18a7d drm/amdgpu: Fix bug where DPM is not enabled after hibernate and resume
commit f878122841 upstream.

Reproducing bug report here:
After hibernating and resuming, DPM is not enabled. This remains the case
even if you test hibernate using the steps here:
https://www.kernel.org/doc/html/latest/power/basic-pm-debugging.html

I debugged the problem, and figured out that in the file hardwaremanager.c,
in the function, phm_enable_dynamic_state_management(), the check
'if (!hwmgr->pp_one_vf && smum_is_dpm_running(hwmgr) && !amdgpu_passthrough(adev) && adev->in_suspend)'
returns true for the hibernate case, and false for the suspend case.

This means that for the hibernate case, the AMDGPU driver doesn't enable DPM
(even though it should) and simply returns from that function.
In the suspend case, it goes ahead and enables DPM, even though it doesn't need to.

I debugged further, and found out that in the case of suspend, for the
CIK/Hawaii GPUs, smum_is_dpm_running(hwmgr) returns false, while in the case of
hibernate, smum_is_dpm_running(hwmgr) returns true.

For CIK, the ci_is_dpm_running() function calls the ci_is_smc_ram_running() function,
which is ultimately used to determine if DPM is currently enabled or not,
and this seems to provide the wrong answer.

I've changed the ci_is_dpm_running() function to instead use the same method that
some other AMD GPU chips do (e.g Fiji), which seems to read the voltage controller.
I've tested on my R9 390 and it seems to work correctly for both suspend and
hibernate use cases, and has been stable so far.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=208839
Signed-off-by: Sandeep Raghuraman <sandy.8925@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Xin Xiong 915ad46bdd drm: fix drm_dp_mst_port refcount leaks in drm_dp_mst_allocate_vcpi
commit a34a0a632d upstream.

drm_dp_mst_allocate_vcpi() invokes
drm_dp_mst_topology_get_port_validated(), which increases the refcount
of the "port".

These reference counting issues take place in two exception handling
paths separately. Either when “slots” is less than 0 or when
drm_dp_init_vcpi() returns a negative value, the function forgets to
reduce the refcnt increased drm_dp_mst_topology_get_port_validated(),
which results in a refcount leak.

Fix these issues by pulling up the error handling when "slots" is less
than 0, and calling drm_dp_mst_topology_put_port() before termination
when drm_dp_init_vcpi() returns a negative value.

Fixes: 1e797f556c ("drm/dp: Split drm_dp_mst_allocate_vcpi")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200719154545.GA41231@xin-virtual-machine
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Marius Iacob f9f53b7c6a drm: Added orientation quirk for ASUS tablet model T103HAF
commit b5ac98cbb8 upstream.

Signed-off-by: Marius Iacob <themariusus@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200801123445.1514567-1-themariusus@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Denis Efremov aeec14061d drm/panfrost: Use kvfree() to free bo->sgts
commit 114427b892 upstream.

Use kvfree() to free bo->sgts, because the memory is allocated with
kvmalloc_array() in panfrost_mmu_map_fault_addr().

Fixes: 187d292920 ("drm/panfrost: Add support for GPU heap allocations")
Cc: stable@vger.kernel.org
Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200608151728.234026-1-efremov@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Tomasz Maciej Nowak a202b42b94 arm64: dts: marvell: espressobin: add ethernet alias
commit 5253cb8c00 upstream.

The maker of this board and its variants, stores MAC address in U-Boot
environment. Add alias for bootloader to recognise, to which ethernet
node inject the factory MAC address.

Signed-off-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
[pali: Backported to 5.4 and older versions]
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Hugh Dickins 0f1c938ef8 khugepaged: retract_page_tables() remember to test exit
commit 18e77600f7 upstream.

Only once have I seen this scenario (and forgot even to notice what forced
the eventual crash): a sequence of "BUG: Bad page map" alerts from
vm_normal_page(), from zap_pte_range() servicing exit_mmap();
pmd:00000000, pte values corresponding to data in physical page 0.

The pte mappings being zapped in this case were supposed to be from a huge
page of ext4 text (but could as well have been shmem): my belief is that
it was racing with collapse_file()'s retract_page_tables(), found *pmd
pointing to a page table, locked it, but *pmd had become 0 by the time
start_pte was decided.

In most cases, that possibility is excluded by holding mmap lock; but
exit_mmap() proceeds without mmap lock.  Most of what's run by khugepaged
checks khugepaged_test_exit() after acquiring mmap lock:
khugepaged_collapse_pte_mapped_thps() and hugepage_vma_revalidate() do so,
for example.  But retract_page_tables() did not: fix that.

The fix is for retract_page_tables() to check khugepaged_test_exit(),
after acquiring mmap lock, before doing anything to the page table.
Getting the mmap lock serializes with __mmput(), which briefly takes and
drops it in __khugepaged_exit(); then the khugepaged_test_exit() check on
mm_users makes sure we don't touch the page table once exit_mmap() might
reach it, since exit_mmap() will be proceeding without mmap lock, not
expecting anyone to be racing with it.

Fixes: f3f0e1d215 ("khugepaged: add support of collapse for tmpfs/shmem pages")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: <stable@vger.kernel.org>	[4.8+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008021215400.27773@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 13:05:39 +02:00
Geert Uytterhoeven e47e005598 sh: landisk: Add missing initialization of sh_io_port_base
[ Upstream commit 0c64a0dce5 ]

The Landisk setup code maps the CF IDE area using ioremap_prot(), and
passes the resulting virtual addresses to the pata_platform driver,
disguising them as I/O port addresses.  Hence the pata_platform driver
translates them again using ioport_map().
As CONFIG_GENERIC_IOMAP=n, and CONFIG_HAS_IOPORT_MAP=y, the
SuperH-specific mapping code in arch/sh/kernel/ioport.c translates
I/O port addresses to virtual addresses by adding sh_io_port_base, which
defaults to -1, thus breaking the assumption of an identity mapping.

Fix this by setting sh_io_port_base to zero.

Fixes: 37b7a97884 ("sh: machvec IO death.")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rich Felker <dalias@libc.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 13:05:38 +02:00
Zhang Rui 64d358a9ad perf/x86/rapl: Fix missing psys sysfs attributes
[ Upstream commit 4bb5fcb97a ]

This fixes a problem introduced by commit:

  5fb5273a90 ("perf/x86/rapl: Use new MSR detection interface")

that perf event sysfs attributes for psys RAPL domain are missing.

Fixes: 5fb5273a90 ("perf/x86/rapl: Use new MSR detection interface")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20200811153149.12242-2-rui.zhang@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 13:05:38 +02:00
Daniel Díaz 5c90739d36 tools build feature: Quote CC and CXX for their arguments
[ Upstream commit fa5c893181 ]

When using a cross-compilation environment, such as OpenEmbedded,
the CC an CXX variables are set to something more than just a
command: there are arguments (such as --sysroot) that need to be
passed on to the compiler so that the right set of headers and
libraries are used.

For the particular case that our systems detected, CC is set to
the following:

  export CC="aarch64-linaro-linux-gcc  --sysroot=/oe/build/tmp/work/machine/perf/1.0-r9/recipe-sysroot"

Without quotes, detection is as follows:

  Auto-detecting system features:
  ...                         dwarf: [ OFF ]
  ...            dwarf_getlocations: [ OFF ]
  ...                         glibc: [ OFF ]
  ...                          gtk2: [ OFF ]
  ...                        libbfd: [ OFF ]
  ...                        libcap: [ OFF ]
  ...                        libelf: [ OFF ]
  ...                       libnuma: [ OFF ]
  ...        numa_num_possible_cpus: [ OFF ]
  ...                       libperl: [ OFF ]
  ...                     libpython: [ OFF ]
  ...                     libcrypto: [ OFF ]
  ...                     libunwind: [ OFF ]
  ...            libdw-dwarf-unwind: [ OFF ]
  ...                          zlib: [ OFF ]
  ...                          lzma: [ OFF ]
  ...                     get_cpuid: [ OFF ]
  ...                           bpf: [ OFF ]
  ...                        libaio: [ OFF ]
  ...                       libzstd: [ OFF ]
  ...        disassembler-four-args: [ OFF ]

  Makefile.config:414: *** No gnu/libc-version.h found, please install glibc-dev[el].  Stop.
  Makefile.perf:230: recipe for target 'sub-make' failed
  make[1]: *** [sub-make] Error 2
  Makefile:69: recipe for target 'all' failed
  make: *** [all] Error 2

With CC and CXX quoted, some of those features are now detected.

Fixes: e3232c2f39 ("tools build feature: Use CC and CXX from parent")
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Reviewed-by: Thomas Hebb <tommyhebb@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Link: http://lore.kernel.org/lkml/20200812221518.2869003-1-daniel.diaz@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 13:05:38 +02:00
Vincent Whitchurch 45989801d7 perf bench mem: Always memset source before memcpy
[ Upstream commit 1beaef29c3 ]

For memcpy, the source pages are memset to zero only when --cycles is
used.  This leads to wildly different results with or without --cycles,
since all sources pages are likely to be mapped to the same zero page
without explicit writes.

Before this fix:

$ export cmd="./perf stat -e LLC-loads -- ./perf bench \
  mem memcpy -s 1024MB -l 100 -f default"
$ $cmd

         2,935,826      LLC-loads
       3.821677452 seconds time elapsed

$ $cmd --cycles

       217,533,436      LLC-loads
       8.616725985 seconds time elapsed

After this fix:

$ $cmd

       214,459,686      LLC-loads
       8.674301124 seconds time elapsed

$ $cmd --cycles

       214,758,651      LLC-loads
       8.644480006 seconds time elapsed

Fixes: 47b5757bac ("perf bench mem: Move boilerplate memory allocation to the infrastructure")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel@axis.com
Link: http://lore.kernel.org/lkml/20200810133404.30829-1-vincent.whitchurch@axis.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21 13:05:38 +02:00