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  1. 21 4月, 2018 13 次提交
    • A
      kasan: add no_sanitize attribute for clang builds · 12c8f25a
      由 Andrey Konovalov 提交于 
      KASAN uses the __no_sanitize_address macro to disable instrumentation of
particular functions.  Right now it's defined only for GCC build, which
causes false positives when clang is used.

This patch adds a definition for clang.

Note, that clang's revision 329612 or higher is required.

[andreyknvl@google.com: remove redundant #ifdef CONFIG_KASAN check]
  Link: http://lkml.kernel.org/r/c79aa31a2a2790f6131ed607c58b0dd45dd62a6c.1523967959.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/4ad725cc903f8534f8c8a60f0daade5e3d674f8d.1523554166.git.andreyknvl@google.comSigned-off-by: NAndrey Konovalov <andreyknvl@google.com>
Acked-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Paul Lawrence <paullawrence@google.com>
Cc: Sandipan Das <sandipan@linux.vnet.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      12c8f25a
    • I
      rapidio: fix rio_dma_transfer error handling · c5157b76
      由 Ioan Nicu 提交于 
      Some of the mport_dma_req structure members were initialized late
inside the do_dma_request() function, just before submitting the
request to the dma engine. But we have some error branches before
that. In case of such an error, the code would return on the error
path and trigger the calling of dma_req_free() with a req structure
which is not completely initialized. This causes a NULL pointer
dereference in dma_req_free().

This patch fixes these error branches by making sure that all
necessary mport_dma_req structure members are initialized in
rio_dma_transfer() immediately after the request structure gets
allocated.

Link: http://lkml.kernel.org/r/20180412150605.GA31409@nokia.com
Fixes: bbd876ad ("rapidio: use a reference count for struct mport_dma_req")
Signed-off-by: NIoan Nicu <ioan.nicu.ext@nokia.com>
Tested-by: NAlexander Sverdlin <alexander.sverdlin@nokia.com>
Acked-by: NAlexandre Bounine <alex.bou9@gmail.com>
Cc: Barry Wood <barry.wood@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Frank Kunz <frank.kunz@nokia.com>
Cc: <stable@vger.kernel.org>	[4.6+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c5157b76
    • N
      mm: enable thp migration for shmem thp · e71769ae
      由 Naoya Horiguchi 提交于 
      My testing for the latest kernel supporting thp migration showed an
infinite loop in offlining the memory block that is filled with shmem
thps.  We can get out of the loop with a signal, but kernel should return
with failure in this case.

What happens in the loop is that scan_movable_pages() repeats returning
the same pfn without any progress.  That's because page migration always
fails for shmem thps.

In memory offline code, memory blocks containing unmovable pages should be
prevented from being offline targets by has_unmovable_pages() inside
start_isolate_page_range().  So it's possible to change migratability for
non-anonymous thps to avoid the issue, but it introduces more complex and
thp-specific handling in migration code, so it might not good.

So this patch is suggesting to fix the issue by enabling thp migration for
shmem thp.  Both of anon/shmem thp are migratable so we don't need
precheck about the type of thps.

Link: http://lkml.kernel.org/r/20180406030706.GA2434@hori1.linux.bs1.fc.nec.co.jp
Fixes: commit 72b39cfc ("mm, memory_hotplug: do not fail offlining too early")
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zi Yan <zi.yan@sent.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e71769ae
    • G
      writeback: safer lock nesting · 2e898e4c
      由 Greg Thelen 提交于 
      lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if
the page's memcg is undergoing move accounting, which occurs when a
process leaves its memcg for a new one that has
memory.move_charge_at_immigrate set.

unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if
the given inode is switching writeback domains.  Switches occur when
enough writes are issued from a new domain.

This existing pattern is thus suspicious:
    lock_page_memcg(page);
    unlocked_inode_to_wb_begin(inode, &locked);
    ...
    unlocked_inode_to_wb_end(inode, locked);
    unlock_page_memcg(page);

If both inode switch and process memcg migration are both in-flight then
unlocked_inode_to_wb_end() will unconditionally enable interrupts while
still holding the lock_page_memcg() irq spinlock.  This suggests the
possibility of deadlock if an interrupt occurs before unlock_page_memcg().

    truncate
    __cancel_dirty_page
    lock_page_memcg
    unlocked_inode_to_wb_begin
    unlocked_inode_to_wb_end
    <interrupts mistakenly enabled>
                                    <interrupt>
                                    end_page_writeback
                                    test_clear_page_writeback
                                    lock_page_memcg
                                    <deadlock>
    unlock_page_memcg

Due to configuration limitations this deadlock is not currently possible
because we don't mix cgroup writeback (a cgroupv2 feature) and
memory.move_charge_at_immigrate (a cgroupv1 feature).

If the kernel is hacked to always claim inode switching and memcg
moving_account, then this script triggers lockup in less than a minute:

  cd /mnt/cgroup/memory
  mkdir a b
  echo 1 > a/memory.move_charge_at_immigrate
  echo 1 > b/memory.move_charge_at_immigrate
  (
    echo $BASHPID > a/cgroup.procs
    while true; do
      dd if=/dev/zero of=/mnt/big bs=1M count=256
    done
  ) &
  while true; do
    sync
  done &
  sleep 1h &
  SLEEP=$!
  while true; do
    echo $SLEEP > a/cgroup.procs
    echo $SLEEP > b/cgroup.procs
  done

The deadlock does not seem possible, so it's debatable if there's any
reason to modify the kernel.  I suggest we should to prevent future
surprises.  And Wang Long said "this deadlock occurs three times in our
environment", so there's more reason to apply this, even to stable.
Stable 4.4 has minor conflicts applying this patch.  For a clean 4.4 patch
see "[PATCH for-4.4] writeback: safer lock nesting"
https://lkml.org/lkml/2018/4/11/146

Wang Long said "this deadlock occurs three times in our environment"

[gthelen@google.com: v4]
  Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com
[akpm@linux-foundation.org: comment tweaks, struct initialization simplification]
Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613
Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com
Fixes: 682aa8e1 ("writeback: implement unlocked_inode_to_wb transaction and use it for stat updates")
Signed-off-by: NGreg Thelen <gthelen@google.com>
Reported-by: NWang Long <wanglong19@meituan.com>
Acked-by: NWang Long <wanglong19@meituan.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: <stable@vger.kernel.org>	[v4.2+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2e898e4c
    • H
      mm, pagemap: fix swap offset value for PMD migration entry · 88c28f24
      由 Huang Ying 提交于 
      The swap offset reported by /proc/<pid>/pagemap may be not correct for
PMD migration entries.  If addr passed into pagemap_pmd_range() isn't
aligned with PMD start address, the swap offset reported doesn't
reflect this.  And in the loop to report information of each sub-page,
the swap offset isn't increased accordingly as that for PFN.

This may happen after opening /proc/<pid>/pagemap and seeking to a page
whose address doesn't align with a PMD start address.  I have verified
this with a simple test program.

BTW: migration swap entries have PFN information, do we need to restrict
whether to show them?

[akpm@linux-foundation.org: fix typo, per Huang, Ying]
Link: http://lkml.kernel.org/r/20180408033737.10897-1-ying.huang@intel.comSigned-off-by: N"Huang, Ying" <ying.huang@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Jerome Glisse" <jglisse@redhat.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      88c28f24
    • M
      mm: fix do_pages_move status handling · 8f175cf5
      由 Michal Hocko 提交于 
      Li Wang has reported that LTP move_pages04 test fails with the current
tree:

LTP move_pages04:
   TFAIL  :  move_pages04.c:143: status[1] is EPERM, expected EFAULT

The test allocates an array of two pages, one is present while the other
is not (resp.  backed by zero page) and it expects EFAULT for the second
page as the man page suggests.  We are reporting EPERM which doesn't make
any sense and this is a result of a bug from cf5f16b23ec9 ("mm: unclutter
THP migration").

do_pages_move tries to handle as many pages in one batch as possible so we
queue all pages with the same node target together and that corresponds to
[start, i] range which is then used to update status array.
add_page_for_migration will correctly notice the zero (resp.  !present)
page and returns with EFAULT which gets written to the status.  But if
this is the last page in the array we do not update start and so the last
store_status after the loop will overwrite the range of the last batch
with NUMA_NO_NODE (which corresponds to EPERM).

Fix this by simply bailing out from the last flush if the pagelist is
empty as there is clearly nothing more to do.

Link: http://lkml.kernel.org/r/20180418121255.334-1-mhocko@kernel.org
Fixes: cf5f16b23ec9 ("mm: unclutter THP migration")
Signed-off-by: NMichal Hocko <mhocko@suse.com>
Reported-by: NLi Wang <liwang@redhat.com>
Tested-by: NLi Wang <liwang@redhat.com>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8f175cf5
    • K
      fork: unconditionally clear stack on fork · e01e8063
      由 Kees Cook 提交于 
      One of the classes of kernel stack content leaks[1] is exposing the
contents of prior heap or stack contents when a new process stack is
allocated.  Normally, those stacks are not zeroed, and the old contents
remain in place.  In the face of stack content exposure flaws, those
contents can leak to userspace.

Fixing this will make the kernel no longer vulnerable to these flaws, as
the stack will be wiped each time a stack is assigned to a new process.
There's not a meaningful change in runtime performance; it almost looks
like it provides a benefit.

Performing back-to-back kernel builds before:
	Run times: 157.86 157.09 158.90 160.94 160.80
	Mean: 159.12
	Std Dev: 1.54

and after:
	Run times: 159.31 157.34 156.71 158.15 160.81
	Mean: 158.46
	Std Dev: 1.46

Instead of making this a build or runtime config, Andy Lutomirski
recommended this just be enabled by default.

[1] A noisy search for many kinds of stack content leaks can be seen here:
https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=linux+kernel+stack+leak

I did some more with perf and cycle counts on running 100,000 execs of
/bin/true.

before:
Cycles: 218858861551 218853036130 214727610969 227656844122 224980542841
Mean:  221015379122.60
Std Dev: 4662486552.47

after:
Cycles: 213868945060 213119275204 211820169456 224426673259 225489986348
Mean:  217745009865.40
Std Dev: 5935559279.99

It continues to look like it's faster, though the deviation is rather
wide, but I'm not sure what I could do that would be less noisy.  I'm
open to ideas!

Link: http://lkml.kernel.org/r/20180221021659.GA37073@beastSigned-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e01e8063
    • D
      vfs: Undo an overly zealous MS_RDONLY -> SB_RDONLY conversion · a9e5b732
      由 David Howells 提交于 
      In do_mount() when the MS_* flags are being converted to MNT_* flags,
MS_RDONLY got accidentally convered to SB_RDONLY.

Undo this change.

Fixes: e462ec50 ("VFS: Differentiate mount flags (MS_*) from internal superblock flags")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a9e5b732
    • D
      afs: Fix server record deletion · 66062592
      由 David Howells 提交于 
      AFS server records get removed from the net->fs_servers tree when
they're deleted, but not from the net->fs_addresses{4,6} lists, which
can lead to an oops in afs_find_server() when a server record has been
removed, for instance during rmmod.

Fix this by deleting the record from the by-address lists before posting
it for RCU destruction.

The reason this hasn't been noticed before is that the fileserver keeps
probing the local cache manager, thereby keeping the service record
alive, so the oops would only happen when a fileserver eventually gets
bored and stops pinging or if the module gets rmmod'd and a call comes
in from the fileserver during the window between the server records
being destroyed and the socket being closed.

The oops looks something like:

  BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
  ...
  Workqueue: kafsd afs_process_async_call [kafs]
  RIP: 0010:afs_find_server+0x271/0x36f [kafs]
  ...
  Call Trace:
   afs_deliver_cb_init_call_back_state3+0x1f2/0x21f [kafs]
   afs_deliver_to_call+0x1ee/0x5e8 [kafs]
   afs_process_async_call+0x5b/0xd0 [kafs]
   process_one_work+0x2c2/0x504
   worker_thread+0x1d4/0x2ac
   kthread+0x11f/0x127
   ret_from_fork+0x24/0x30

Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      66062592
    • L
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · a72db42c
      由 Linus Torvalds 提交于 
      Pull networking fixes from David Miller:

 1) Unbalanced refcounting in TIPC, from Jon Maloy.

 2) Only allow TCP_MD5SIG to be set on sockets in close or listen state.
    Once the connection is established it makes no sense to change this.
    From Eric Dumazet.

 3) Missing attribute validation in neigh_dump_table(), also from Eric
    Dumazet.

 4) Fix address comparisons in SCTP, from Xin Long.

 5) Neigh proxy table clearing can deadlock, from Wolfgang Bumiller.

 6) Fix tunnel refcounting in l2tp, from Guillaume Nault.

 7) Fix double list insert in team driver, from Paolo Abeni.

 8) af_vsock.ko module was accidently made unremovable, from Stefan
    Hajnoczi.

 9) Fix reference to freed llc_sap object in llc stack, from Cong Wang.

10) Don't assume netdevice struct is DMA'able memory in virtio_net
    driver, from Michael S. Tsirkin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (62 commits)
  net/smc: fix shutdown in state SMC_LISTEN
  bnxt_en: Fix memory fault in bnxt_ethtool_init()
  virtio_net: sparse annotation fix
  virtio_net: fix adding vids on big-endian
  virtio_net: split out ctrl buffer
  net: hns: Avoid action name truncation
  docs: ip-sysctl.txt: fix name of some ipv6 variables
  vmxnet3: fix incorrect dereference when rxvlan is disabled
  llc: hold llc_sap before release_sock()
  MAINTAINERS: Direct networking documentation changes to netdev
  atm: iphase: fix spelling mistake: "Tansmit" -> "Transmit"
  net: qmi_wwan: add Wistron Neweb D19Q1
  net: caif: fix spelling mistake "UKNOWN" -> "UNKNOWN"
  net: stmmac: Disable ACS Feature for GMAC >= 4
  net: mvpp2: Fix DMA address mask size
  net: change the comment of dev_mc_init
  net: qualcomm: rmnet: Fix warning seen with fill_info
  tun: fix vlan packet truncation
  tipc: fix infinite loop when dumping link monitor summary
  tipc: fix use-after-free in tipc_nametbl_stop
  ...
      a72db42c
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · b9abdcfd
      由 Linus Torvalds 提交于 
      Pull vfs fixes from Al Viro:
 "Assorted fixes.

  Some of that is only a matter with fault injection (broken handling of
  small allocation failure in various mount-related places), but the
  last one is a root-triggerable stack overflow, and combined with
  userns it gets really nasty ;-/"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Don't leak MNT_INTERNAL away from internal mounts
  mm,vmscan: Allow preallocating memory for register_shrinker().
  rpc_pipefs: fix double-dput()
  orangefs_kill_sb(): deal with allocation failures
  jffs2_kill_sb(): deal with failed allocations
  hypfs_kill_super(): deal with failed allocations
      b9abdcfd
    • L
      Merge tag 'ecryptfs-4.17-rc2-fixes' of... · 43f70c96
      由 Linus Torvalds 提交于 
      Merge tag 'ecryptfs-4.17-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull eCryptfs fixes from Tyler Hicks:
 "Minor cleanups and a bug fix to completely ignore unencrypted
  filenames in the lower filesystem when filename encryption is enabled
  at the eCryptfs layer"

* tag 'ecryptfs-4.17-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: don't pass up plaintext names when using filename encryption
  ecryptfs: fix spelling mistake: "cadidate" -> "candidate"
  ecryptfs: lookup: Don't check if mount_crypt_stat is NULL
      43f70c96
    • L
      Merge tag 'for_v4.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs · 0d9cf33b
      由 Linus Torvalds 提交于 
       - isofs memory leak fix

 - two fsnotify fixes of event mask handling

 - udf fix of UTF-16 handling

 - couple other smaller cleanups

* tag 'for_v4.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix leak of UTF-16 surrogates into encoded strings
  fs: ext2: Adding new return type vm_fault_t
  isofs: fix potential memory leak in mount option parsing
  MAINTAINERS: add an entry for FSNOTIFY infrastructure
  fsnotify: fix typo in a comment about mark->g_list
  fsnotify: fix ignore mask logic in send_to_group()
  isofs compress: Remove VLA usage
  fs: quota: Replace GFP_ATOMIC with GFP_KERNEL in dquot_init
  fanotify: fix logic of events on child
      0d9cf33b
  3. 20 4月, 2018 24 次提交
  5. 19 4月, 2018 3 次提交
    • J
      HID: i2c-hid: fix inverted return value from i2c_hid_command() · b658912c
      由 Jiri Kosina 提交于 
      i2c_hid_command() returns non-zero in error cases (the actual
errno). Error handling in for I2C_HID_QUIRK_RESEND_REPORT_DESCR
case in i2c_hid_resume() had the check inverted; fix that.

Fixes: 3e83eda4 ("HID: i2c-hid: Fix resume issue on Raydium touchscreen device")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>
      b658912c
    • M
      powerpc/kvm: Fix lockups when running KVM guests on Power8 · 56376c58
      由 Michael Ellerman 提交于 
      When running KVM guests on Power8 we can see a lockup where one CPU
stops responding. This often leads to a message such as:

  watchdog: CPU 136 detected hard LOCKUP on other CPUs 72
  Task dump for CPU 72:
  qemu-system-ppc R  running task    10560 20917  20908 0x00040004

And then backtraces on other CPUs, such as:

  Task dump for CPU 48:
  ksmd            R  running task    10032  1519      2 0x00000804
  Call Trace:
    ...
    --- interrupt: 901 at smp_call_function_many+0x3c8/0x460
        LR = smp_call_function_many+0x37c/0x460
    pmdp_invalidate+0x100/0x1b0
    __split_huge_pmd+0x52c/0xdb0
    try_to_unmap_one+0x764/0x8b0
    rmap_walk_anon+0x15c/0x370
    try_to_unmap+0xb4/0x170
    split_huge_page_to_list+0x148/0xa30
    try_to_merge_one_page+0xc8/0x990
    try_to_merge_with_ksm_page+0x74/0xf0
    ksm_scan_thread+0x10ec/0x1ac0
    kthread+0x160/0x1a0
    ret_from_kernel_thread+0x5c/0x78

This is caused by commit 8c1c7fb0 ("powerpc/64s/idle: avoid sync
for KVM state when waking from idle"), which added a check in
pnv_powersave_wakeup() to see if the kvm_hstate.hwthread_state is
already set to KVM_HWTHREAD_IN_KERNEL, and if so to skip the store and
test of kvm_hstate.hwthread_req.

The problem is that the primary does not set KVM_HWTHREAD_IN_KVM when
entering the guest, so it can then come out to cede with
KVM_HWTHREAD_IN_KERNEL set. It can then go idle in kvm_do_nap after
setting hwthread_req to 1, but because hwthread_state is still
KVM_HWTHREAD_IN_KERNEL we will skip the test of hwthread_req when we
wake up from idle and won't go to kvm_start_guest. From there the
thread will return somewhere garbage and crash.

Fix it by skipping the store of hwthread_state, but not the test of
hwthread_req, when coming out of idle. It's OK to skip the sync in
that case because hwthread_req will have been set on the same thread,
so there is no synchronisation required.

Fixes: 8c1c7fb0 ("powerpc/64s/idle: avoid sync for KVM state when waking from idle")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      56376c58
    • M
      powerpc/eeh: Fix enabling bridge MMIO windows · 13a83eac
      由 Michael Neuling 提交于 
      On boot we save the configuration space of PCIe bridges. We do this so
when we get an EEH event and everything gets reset that we can restore
them.

Unfortunately we save this state before we've enabled the MMIO space
on the bridges. Hence if we have to reset the bridge when we come back
MMIO is not enabled and we end up taking an PE freeze when the driver
starts accessing again.

This patch forces the memory/MMIO and bus mastering on when restoring
bridges on EEH. Ideally we'd do this correctly by saving the
configuration space writes later, but that will have to come later in
a larger EEH rewrite. For now we have this simple fix.

The original bug can be triggered on a boston machine by doing:
  echo 0x8000000000000000 > /sys/kernel/debug/powerpc/PCI0001/err_injct_outbound
On boston, this PHB has a PCIe switch on it.  Without this patch,
you'll see two EEH events, 1 expected and 1 the failure we are fixing
here. The second EEH event causes the anything under the PHB to
disappear (i.e. the i40e eth).

With this patch, only 1 EEH event occurs and devices properly recover.

Fixes: 652defed ("powerpc/eeh: Check PCIe link after reset")
Cc: stable@vger.kernel.org # v3.11+
Reported-by: NPridhiviraj Paidipeddi <ppaidipe@linux.vnet.ibm.com>
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Acked-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      13a83eac