linux-stable.git, branch v4.9.153 Linux kernel stable tree Linux 4.9.153 2019-01-26T08:38:36+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2019-01-26T08:38:36+00:00 189b75ad3fc2d4a0d40a818ca298526d254ccdc4 






locking/qspinlock: Pull in asm/byteorder.h to ensure correct endianness
2019-01-26T08:38:36+00:00

Dave Airlie
airlied@redhat.com

2019-01-24T18:54:15+00:00

4b527f25a4ac64c0d17c882cdf8322be66f31611

This commit is not required upstream, but is required for the 4.9.y
stable series.

Upstream commit 101110f6271c ("Kbuild: always define endianess in
kconfig.h") ensures that either __LITTLE_ENDIAN or __BIG_ENDIAN is
defined to reflect the endianness of the target CPU architecture
regardless of whether or not <asm/byteorder.h> has been #included. The
upstream definition of 'struct qspinlock' relies on this property.

Unfortunately, the 4.9.y stable series does not provide this guarantee,
so the 'spin_unlock()' routine can erroneously treat the underlying
lockword as big-endian on little-endian architectures using native
qspinlock (i.e. x86_64 without PV) if the caller has not included
<asm/byteorder.h>. This can lead to hangs such as the one in
'i915_gem_request()' reported via bugzilla:

  https://bugzilla.kernel.org/show_bug.cgi?id=202063

Fix the issue by ensuring that <asm/byteorder.h> is #included in
<asm/qspinlock_types.h>, where 'struct qspinlock' is defined.

Cc: <stable@vger.kernel.org> # 4.9
Signed-off-by: Dave Airlie <airlied@redhat.com>
[will: wrote commit message]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






This commit is not required upstream, but is required for the 4.9.y
stable series.

Upstream commit 101110f6271c ("Kbuild: always define endianess in
kconfig.h") ensures that either __LITTLE_ENDIAN or __BIG_ENDIAN is
defined to reflect the endianness of the target CPU architecture
regardless of whether or not <asm/byteorder.h> has been #included. The
upstream definition of 'struct qspinlock' relies on this property.

Unfortunately, the 4.9.y stable series does not provide this guarantee,
so the 'spin_unlock()' routine can erroneously treat the underlying
lockword as big-endian on little-endian architectures using native
qspinlock (i.e. x86_64 without PV) if the caller has not included
<asm/byteorder.h>. This can lead to hangs such as the one in
'i915_gem_request()' reported via bugzilla:

  https://bugzilla.kernel.org/show_bug.cgi?id=202063

Fix the issue by ensuring that <asm/byteorder.h> is #included in
<asm/qspinlock_types.h>, where 'struct qspinlock' is defined.

Cc: <stable@vger.kernel.org> # 4.9
Signed-off-by: Dave Airlie <airlied@redhat.com>
[will: wrote commit message]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








ipmi:ssif: Fix handling of multi-part return messages
2019-01-26T08:38:36+00:00

Corey Minyard
cminyard@mvista.com

2018-11-16T15:59:21+00:00

cac2590d2582c04f995c2b1cd2c30d8a0c11b36e

commit 7d6380cd40f7993f75c4bde5b36f6019237e8719 upstream.

The block number was not being compared right, it was off by one
when checking the response.

Some statistics wouldn't be incremented properly in some cases.

Check to see if that middle-part messages always have 31 bytes of
data.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>






commit 7d6380cd40f7993f75c4bde5b36f6019237e8719 upstream.

The block number was not being compared right, it was off by one
when checking the response.

Some statistics wouldn't be incremented properly in some cases.

Check to see if that middle-part messages always have 31 bytes of
data.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>








mm, proc: be more verbose about unstable VMA flags in /proc/<pid>/smaps
2019-01-26T08:38:36+00:00

Michal Hocko
mhocko@suse.com

2018-12-28T08:38:17+00:00

28aeb4c95f8a8da9c65461979fbb8eddf7d4f56f

[ Upstream commit 7550c6079846a24f30d15ac75a941c8515dbedfb ]

Patch series "THP eligibility reporting via proc".

This series of three patches aims at making THP eligibility reporting much
more robust and long term sustainable.  The trigger for the change is a
regression report [2] and the long follow up discussion.  In short the
specific application didn't have good API to query whether a particular
mapping can be backed by THP so it has used VMA flags to workaround that.
These flags represent a deep internal state of VMAs and as such they
should be used by userspace with a great deal of caution.

A similar has happened for [3] when users complained that VM_MIXEDMAP is
no longer set on DAX mappings.  Again a lack of a proper API led to an
abuse.

The first patch in the series tries to emphasise that that the semantic of
flags might change and any application consuming those should be really
careful.

The remaining two patches provide a more suitable interface to address [2]
and provide a consistent API to query the THP status both for each VMA and
process wide as well.  [1]

http://lkml.kernel.org/r/20181120103515.25280-1-mhocko@kernel.org [2]
http://lkml.kernel.org/r/http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
[3] http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz

This patch (of 3):

Even though vma flags exported via /proc/<pid>/smaps are explicitly
documented to be not guaranteed for future compatibility the warning
doesn't go far enough because it doesn't mention semantic changes to those
flags.  And they are important as well because these flags are a deep
implementation internal to the MM code and the semantic might change at
any time.

Let's consider two recent examples:
http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz
: commit e1fb4a086495 "dax: remove VM_MIXEDMAP for fsdax and device dax" has
: removed VM_MIXEDMAP flag from DAX VMAs. Now our testing shows that in the
: mean time certain customer of ours started poking into /proc/<pid>/smaps
: and looks at VMA flags there and if VM_MIXEDMAP is missing among the VMA
: flags, the application just fails to start complaining that DAX support is
: missing in the kernel.

http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
: Commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active")
: introduced a regression in that userspace cannot always determine the set
: of vmas where thp is ineligible.
: Userspace relies on the "nh" flag being emitted as part of /proc/pid/smaps
: to determine if a vma is eligible to be backed by hugepages.
: Previous to this commit, prctl(PR_SET_THP_DISABLE, 1) would cause thp to
: be disabled and emit "nh" as a flag for the corresponding vmas as part of
: /proc/pid/smaps.  After the commit, thp is disabled by means of an mm
: flag and "nh" is not emitted.
: This causes smaps parsing libraries to assume a vma is eligible for thp
: and ends up puzzling the user on why its memory is not backed by thp.

In both cases userspace was relying on a semantic of a specific VMA flag.
The primary reason why that happened is a lack of a proper interface.
While this has been worked on and it will be fixed properly, it seems that
our wording could see some refinement and be more vocal about semantic
aspect of these flags as well.

Link: http://lkml.kernel.org/r/20181211143641.3503-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Oppenheimer <bepvte@gmail.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 7550c6079846a24f30d15ac75a941c8515dbedfb ]

Patch series "THP eligibility reporting via proc".

This series of three patches aims at making THP eligibility reporting much
more robust and long term sustainable.  The trigger for the change is a
regression report [2] and the long follow up discussion.  In short the
specific application didn't have good API to query whether a particular
mapping can be backed by THP so it has used VMA flags to workaround that.
These flags represent a deep internal state of VMAs and as such they
should be used by userspace with a great deal of caution.

A similar has happened for [3] when users complained that VM_MIXEDMAP is
no longer set on DAX mappings.  Again a lack of a proper API led to an
abuse.

The first patch in the series tries to emphasise that that the semantic of
flags might change and any application consuming those should be really
careful.

The remaining two patches provide a more suitable interface to address [2]
and provide a consistent API to query the THP status both for each VMA and
process wide as well.  [1]

http://lkml.kernel.org/r/20181120103515.25280-1-mhocko@kernel.org [2]
http://lkml.kernel.org/r/http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
[3] http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz

This patch (of 3):

Even though vma flags exported via /proc/<pid>/smaps are explicitly
documented to be not guaranteed for future compatibility the warning
doesn't go far enough because it doesn't mention semantic changes to those
flags.  And they are important as well because these flags are a deep
implementation internal to the MM code and the semantic might change at
any time.

Let's consider two recent examples:
http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz
: commit e1fb4a086495 "dax: remove VM_MIXEDMAP for fsdax and device dax" has
: removed VM_MIXEDMAP flag from DAX VMAs. Now our testing shows that in the
: mean time certain customer of ours started poking into /proc/<pid>/smaps
: and looks at VMA flags there and if VM_MIXEDMAP is missing among the VMA
: flags, the application just fails to start complaining that DAX support is
: missing in the kernel.

http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
: Commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active")
: introduced a regression in that userspace cannot always determine the set
: of vmas where thp is ineligible.
: Userspace relies on the "nh" flag being emitted as part of /proc/pid/smaps
: to determine if a vma is eligible to be backed by hugepages.
: Previous to this commit, prctl(PR_SET_THP_DISABLE, 1) would cause thp to
: be disabled and emit "nh" as a flag for the corresponding vmas as part of
: /proc/pid/smaps.  After the commit, thp is disabled by means of an mm
: flag and "nh" is not emitted.
: This causes smaps parsing libraries to assume a vma is eligible for thp
: and ends up puzzling the user on why its memory is not backed by thp.

In both cases userspace was relying on a semantic of a specific VMA flag.
The primary reason why that happened is a lack of a proper interface.
While this has been worked on and it will be fixed properly, it seems that
our wording could see some refinement and be more vocal about semantic
aspect of these flags as well.

Link: http://lkml.kernel.org/r/20181211143641.3503-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Oppenheimer <bepvte@gmail.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>







mm/page-writeback.c: don't break integrity writeback on ->writepage() error
2019-01-26T08:38:35+00:00

Brian Foster
bfoster@redhat.com

2018-12-28T08:37:20+00:00

c6e4be626e83a3e61004c944bb5aa210ec3447cc

[ Upstream commit 3fa750dcf29e8606e3969d13d8e188cc1c0f511d ]

write_cache_pages() is used in both background and integrity writeback
scenarios by various filesystems.  Background writeback is mostly
concerned with cleaning a certain number of dirty pages based on various
mm heuristics.  It may not write the full set of dirty pages or wait for
I/O to complete.  Integrity writeback is responsible for persisting a set
of dirty pages before the writeback job completes.  For example, an
fsync() call must perform integrity writeback to ensure data is on disk
before the call returns.

write_cache_pages() unconditionally breaks out of its processing loop in
the event of a ->writepage() error.  This is fine for background
writeback, which had no strict requirements and will eventually come
around again.  This can cause problems for integrity writeback on
filesystems that might need to clean up state associated with failed page
writeouts.  For example, XFS performs internal delayed allocation
accounting before returning a ->writepage() error, where applicable.  If
the current writeback happens to be associated with an unmount and
write_cache_pages() completes the writeback prematurely due to error, the
filesystem is unmounted in an inconsistent state if dirty+delalloc pages
still exist.

To handle this problem, update write_cache_pages() to always process the
full set of pages for integrity writeback regardless of ->writepage()
errors.  Save the first encountered error and return it to the caller once
complete.  This facilitates XFS (or any other fs that expects integrity
writeback to process the entire set of dirty pages) to clean up its
internal state completely in the event of persistent mapping errors.
Background writeback continues to exit on the first error encountered.

[akpm@linux-foundation.org: fix typo in comment]
Link: http://lkml.kernel.org/r/20181116134304.32440-1-bfoster@redhat.com
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 3fa750dcf29e8606e3969d13d8e188cc1c0f511d ]

write_cache_pages() is used in both background and integrity writeback
scenarios by various filesystems.  Background writeback is mostly
concerned with cleaning a certain number of dirty pages based on various
mm heuristics.  It may not write the full set of dirty pages or wait for
I/O to complete.  Integrity writeback is responsible for persisting a set
of dirty pages before the writeback job completes.  For example, an
fsync() call must perform integrity writeback to ensure data is on disk
before the call returns.

write_cache_pages() unconditionally breaks out of its processing loop in
the event of a ->writepage() error.  This is fine for background
writeback, which had no strict requirements and will eventually come
around again.  This can cause problems for integrity writeback on
filesystems that might need to clean up state associated with failed page
writeouts.  For example, XFS performs internal delayed allocation
accounting before returning a ->writepage() error, where applicable.  If
the current writeback happens to be associated with an unmount and
write_cache_pages() completes the writeback prematurely due to error, the
filesystem is unmounted in an inconsistent state if dirty+delalloc pages
still exist.

To handle this problem, update write_cache_pages() to always process the
full set of pages for integrity writeback regardless of ->writepage()
errors.  Save the first encountered error and return it to the caller once
complete.  This facilitates XFS (or any other fs that expects integrity
writeback to process the entire set of dirty pages) to clean up its
internal state completely in the event of persistent mapping errors.
Background writeback continues to exit on the first error encountered.

[akpm@linux-foundation.org: fix typo in comment]
Link: http://lkml.kernel.org/r/20181116134304.32440-1-bfoster@redhat.com
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>







ocfs2: fix panic due to unrecovered local alloc
2019-01-26T08:38:35+00:00

Junxiao Bi
junxiao.bi@oracle.com

2018-12-28T08:32:50+00:00

3cc44695613e98bbe3df60fc5297a3a9b55e45a4

[ Upstream commit 532e1e54c8140188e192348c790317921cb2dc1c ]

mount.ocfs2 ignore the inconsistent error that journal is clean but
local alloc is unrecovered.  After mount, local alloc not empty, then
reserver cluster didn't alloc a new local alloc window, reserveration
map is empty(ocfs2_reservation_map.m_bitmap_len = 0), that triggered the
following panic.

This issue was reported at

  https://oss.oracle.com/pipermail/ocfs2-devel/2015-May/010854.html

and was advised to fixed during mount.  But this is a very unusual
inconsistent state, usually journal dirty flag should be cleared at the
last stage of umount until every other things go right.  We may need do
further debug to check that.  Any way to avoid possible futher
corruption, mount should be abort and fsck should be run.

  (mount.ocfs2,1765,1):ocfs2_load_local_alloc:353 ERROR: Local alloc hasn't been recovered!
  found = 6518, set = 6518, taken = 8192, off = 15912372
  ocfs2: Mounting device (202,64) on (node 0, slot 3) with ordered data mode.
  o2dlm: Joining domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 8 ) 8 nodes
  ocfs2: Mounting device (202,80) on (node 0, slot 3) with ordered data mode.
  o2hb: Region 89CEAC63CC4F4D03AC185B44E0EE0F3F (xvdf) is now a quorum device
  o2net: Accepted connection from node yvwsoa17p (num 7) at 172.22.77.88:7777
  o2dlm: Node 7 joins domain 64FE421C8C984E6D96ED12C55FEE2435 ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  o2dlm: Node 7 joins domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  ------------[ cut here ]------------
  kernel BUG at fs/ocfs2/reservations.c:507!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: ocfs2 rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs fscache lockd grace ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sunrpc ipt_REJECT nf_reject_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 ovmapi ppdev parport_pc parport xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea acpi_cpufreq pcspkr i2c_piix4 i2c_core sg ext4 jbd2 mbcache2 sr_mod cdrom xen_blkfront pata_acpi ata_generic ata_piix floppy dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 4349 Comm: startWebLogic.s Not tainted 4.1.12-124.19.2.el6uek.x86_64 #2
  Hardware name: Xen HVM domU, BIOS 4.4.4OVM 09/06/2018
  task: ffff8803fb04e200 ti: ffff8800ea4d8000 task.ti: ffff8800ea4d8000
  RIP: 0010:[<ffffffffa05e96a8>]  [<ffffffffa05e96a8>] __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
  Call Trace:
    ocfs2_resmap_resv_bits+0x10d/0x400 [ocfs2]
    ocfs2_claim_local_alloc_bits+0xd0/0x640 [ocfs2]
    __ocfs2_claim_clusters+0x178/0x360 [ocfs2]
    ocfs2_claim_clusters+0x1f/0x30 [ocfs2]
    ocfs2_convert_inline_data_to_extents+0x634/0xa60 [ocfs2]
    ocfs2_write_begin_nolock+0x1c6/0x1da0 [ocfs2]
    ocfs2_write_begin+0x13e/0x230 [ocfs2]
    generic_perform_write+0xbf/0x1c0
    __generic_file_write_iter+0x19c/0x1d0
    ocfs2_file_write_iter+0x589/0x1360 [ocfs2]
    __vfs_write+0xb8/0x110
    vfs_write+0xa9/0x1b0
    SyS_write+0x46/0xb0
    system_call_fastpath+0x18/0xd7
  Code: ff ff 8b 75 b8 39 75 b0 8b 45 c8 89 45 98 0f 84 e5 fe ff ff 45 8b 74 24 18 41 8b 54 24 1c e9 56 fc ff ff 85 c0 0f 85 48 ff ff ff <0f> 0b 48 8b 05 cf c3 de ff 48 ba 00 00 00 00 00 00 00 10 48 85
  RIP   __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
   RSP <ffff8800ea4db668>
  ---[ end trace 566f07529f2edf3c ]---
  Kernel panic - not syncing: Fatal exception
  Kernel Offset: disabled

Link: http://lkml.kernel.org/r/20181121020023.3034-2-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 532e1e54c8140188e192348c790317921cb2dc1c ]

mount.ocfs2 ignore the inconsistent error that journal is clean but
local alloc is unrecovered.  After mount, local alloc not empty, then
reserver cluster didn't alloc a new local alloc window, reserveration
map is empty(ocfs2_reservation_map.m_bitmap_len = 0), that triggered the
following panic.

This issue was reported at

  https://oss.oracle.com/pipermail/ocfs2-devel/2015-May/010854.html

and was advised to fixed during mount.  But this is a very unusual
inconsistent state, usually journal dirty flag should be cleared at the
last stage of umount until every other things go right.  We may need do
further debug to check that.  Any way to avoid possible futher
corruption, mount should be abort and fsck should be run.

  (mount.ocfs2,1765,1):ocfs2_load_local_alloc:353 ERROR: Local alloc hasn't been recovered!
  found = 6518, set = 6518, taken = 8192, off = 15912372
  ocfs2: Mounting device (202,64) on (node 0, slot 3) with ordered data mode.
  o2dlm: Joining domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 8 ) 8 nodes
  ocfs2: Mounting device (202,80) on (node 0, slot 3) with ordered data mode.
  o2hb: Region 89CEAC63CC4F4D03AC185B44E0EE0F3F (xvdf) is now a quorum device
  o2net: Accepted connection from node yvwsoa17p (num 7) at 172.22.77.88:7777
  o2dlm: Node 7 joins domain 64FE421C8C984E6D96ED12C55FEE2435 ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  o2dlm: Node 7 joins domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  ------------[ cut here ]------------
  kernel BUG at fs/ocfs2/reservations.c:507!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: ocfs2 rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs fscache lockd grace ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sunrpc ipt_REJECT nf_reject_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 ovmapi ppdev parport_pc parport xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea acpi_cpufreq pcspkr i2c_piix4 i2c_core sg ext4 jbd2 mbcache2 sr_mod cdrom xen_blkfront pata_acpi ata_generic ata_piix floppy dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 4349 Comm: startWebLogic.s Not tainted 4.1.12-124.19.2.el6uek.x86_64 #2
  Hardware name: Xen HVM domU, BIOS 4.4.4OVM 09/06/2018
  task: ffff8803fb04e200 ti: ffff8800ea4d8000 task.ti: ffff8800ea4d8000
  RIP: 0010:[<ffffffffa05e96a8>]  [<ffffffffa05e96a8>] __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
  Call Trace:
    ocfs2_resmap_resv_bits+0x10d/0x400 [ocfs2]
    ocfs2_claim_local_alloc_bits+0xd0/0x640 [ocfs2]
    __ocfs2_claim_clusters+0x178/0x360 [ocfs2]
    ocfs2_claim_clusters+0x1f/0x30 [ocfs2]
    ocfs2_convert_inline_data_to_extents+0x634/0xa60 [ocfs2]
    ocfs2_write_begin_nolock+0x1c6/0x1da0 [ocfs2]
    ocfs2_write_begin+0x13e/0x230 [ocfs2]
    generic_perform_write+0xbf/0x1c0
    __generic_file_write_iter+0x19c/0x1d0
    ocfs2_file_write_iter+0x589/0x1360 [ocfs2]
    __vfs_write+0xb8/0x110
    vfs_write+0xa9/0x1b0
    SyS_write+0x46/0xb0
    system_call_fastpath+0x18/0xd7
  Code: ff ff 8b 75 b8 39 75 b0 8b 45 c8 89 45 98 0f 84 e5 fe ff ff 45 8b 74 24 18 41 8b 54 24 1c e9 56 fc ff ff 85 c0 0f 85 48 ff ff ff <0f> 0b 48 8b 05 cf c3 de ff 48 ba 00 00 00 00 00 00 00 10 48 85
  RIP   __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
   RSP <ffff8800ea4db668>
  ---[ end trace 566f07529f2edf3c ]---
  Kernel panic - not syncing: Fatal exception
  Kernel Offset: disabled

Link: http://lkml.kernel.org/r/20181121020023.3034-2-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>







scsi: megaraid: fix out-of-bound array accesses
2019-01-26T08:38:35+00:00

Qian Cai
cai@lca.pw

2018-12-13T13:27:27+00:00

7e4c9c4738231f4b96e819e31c94b877d2cf5178

[ Upstream commit c7a082e4242fd8cd21a441071e622f87c16bdacc ]

UBSAN reported those with MegaRAID SAS-3 3108,

[   77.467308] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
[   77.475402] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
[   77.481677] CPU: 16 PID: 333 Comm: kworker/16:1 Not tainted 4.20.0-rc5+ #1
[   77.488556] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
[   77.495791] Workqueue: events work_for_cpu_fn
[   77.500154] Call trace:
[   77.502610]  dump_backtrace+0x0/0x2c8
[   77.506279]  show_stack+0x24/0x30
[   77.509604]  dump_stack+0x118/0x19c
[   77.513098]  ubsan_epilogue+0x14/0x60
[   77.516765]  __ubsan_handle_out_of_bounds+0xfc/0x13c
[   77.521767]  mr_update_load_balance_params+0x150/0x158 [megaraid_sas]
[   77.528230]  MR_ValidateMapInfo+0x2cc/0x10d0 [megaraid_sas]
[   77.533825]  megasas_get_map_info+0x244/0x2f0 [megaraid_sas]
[   77.539505]  megasas_init_adapter_fusion+0x9b0/0xf48 [megaraid_sas]
[   77.545794]  megasas_init_fw+0x1ab4/0x3518 [megaraid_sas]
[   77.551212]  megasas_probe_one+0x2c4/0xbe0 [megaraid_sas]
[   77.556614]  local_pci_probe+0x7c/0xf0
[   77.560365]  work_for_cpu_fn+0x34/0x50
[   77.564118]  process_one_work+0x61c/0xf08
[   77.568129]  worker_thread+0x534/0xa70
[   77.571882]  kthread+0x1c8/0x1d0
[   77.575114]  ret_from_fork+0x10/0x1c

[   89.240332] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
[   89.248426] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
[   89.254700] CPU: 16 PID: 95 Comm: kworker/u130:0 Not tainted 4.20.0-rc5+ #1
[   89.261665] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
[   89.268903] Workqueue: events_unbound async_run_entry_fn
[   89.274222] Call trace:
[   89.276680]  dump_backtrace+0x0/0x2c8
[   89.280348]  show_stack+0x24/0x30
[   89.283671]  dump_stack+0x118/0x19c
[   89.287167]  ubsan_epilogue+0x14/0x60
[   89.290835]  __ubsan_handle_out_of_bounds+0xfc/0x13c
[   89.295828]  MR_LdRaidGet+0x50/0x58 [megaraid_sas]
[   89.300638]  megasas_build_io_fusion+0xbb8/0xd90 [megaraid_sas]
[   89.306576]  megasas_build_and_issue_cmd_fusion+0x138/0x460 [megaraid_sas]
[   89.313468]  megasas_queue_command+0x398/0x3d0 [megaraid_sas]
[   89.319222]  scsi_dispatch_cmd+0x1dc/0x8a8
[   89.323321]  scsi_request_fn+0x8e8/0xdd0
[   89.327249]  __blk_run_queue+0xc4/0x158
[   89.331090]  blk_execute_rq_nowait+0xf4/0x158
[   89.335449]  blk_execute_rq+0xdc/0x158
[   89.339202]  __scsi_execute+0x130/0x258
[   89.343041]  scsi_probe_and_add_lun+0x2fc/0x1488
[   89.347661]  __scsi_scan_target+0x1cc/0x8c8
[   89.351848]  scsi_scan_channel.part.3+0x8c/0xc0
[   89.356382]  scsi_scan_host_selected+0x130/0x1f0
[   89.361002]  do_scsi_scan_host+0xd8/0xf0
[   89.364927]  do_scan_async+0x9c/0x320
[   89.368594]  async_run_entry_fn+0x138/0x420
[   89.372780]  process_one_work+0x61c/0xf08
[   89.376793]  worker_thread+0x13c/0xa70
[   89.380546]  kthread+0x1c8/0x1d0
[   89.383778]  ret_from_fork+0x10/0x1c

This is because when populating Driver Map using firmware raid map, all
non-existing VDs set their ldTgtIdToLd to 0xff, so it can be skipped later.

From drivers/scsi/megaraid/megaraid_sas_base.c ,
memset(instance->ld_ids, 0xff, MEGASAS_MAX_LD_IDS);

From drivers/scsi/megaraid/megaraid_sas_fp.c ,
/* For non existing VDs, iterate to next VD*/
if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
	continue;

However, there are a few places that failed to skip those non-existing VDs
due to off-by-one errors. Then, those 0xff leaked into MR_LdRaidGet(0xff,
map) and triggered the out-of-bound accesses.

Fixes: 51087a8617fe ("megaraid_sas : Extended VD support")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit c7a082e4242fd8cd21a441071e622f87c16bdacc ]

UBSAN reported those with MegaRAID SAS-3 3108,

[   77.467308] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
[   77.475402] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
[   77.481677] CPU: 16 PID: 333 Comm: kworker/16:1 Not tainted 4.20.0-rc5+ #1
[   77.488556] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
[   77.495791] Workqueue: events work_for_cpu_fn
[   77.500154] Call trace:
[   77.502610]  dump_backtrace+0x0/0x2c8
[   77.506279]  show_stack+0x24/0x30
[   77.509604]  dump_stack+0x118/0x19c
[   77.513098]  ubsan_epilogue+0x14/0x60
[   77.516765]  __ubsan_handle_out_of_bounds+0xfc/0x13c
[   77.521767]  mr_update_load_balance_params+0x150/0x158 [megaraid_sas]
[   77.528230]  MR_ValidateMapInfo+0x2cc/0x10d0 [megaraid_sas]
[   77.533825]  megasas_get_map_info+0x244/0x2f0 [megaraid_sas]
[   77.539505]  megasas_init_adapter_fusion+0x9b0/0xf48 [megaraid_sas]
[   77.545794]  megasas_init_fw+0x1ab4/0x3518 [megaraid_sas]
[   77.551212]  megasas_probe_one+0x2c4/0xbe0 [megaraid_sas]
[   77.556614]  local_pci_probe+0x7c/0xf0
[   77.560365]  work_for_cpu_fn+0x34/0x50
[   77.564118]  process_one_work+0x61c/0xf08
[   77.568129]  worker_thread+0x534/0xa70
[   77.571882]  kthread+0x1c8/0x1d0
[   77.575114]  ret_from_fork+0x10/0x1c

[   89.240332] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
[   89.248426] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
[   89.254700] CPU: 16 PID: 95 Comm: kworker/u130:0 Not tainted 4.20.0-rc5+ #1
[   89.261665] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
[   89.268903] Workqueue: events_unbound async_run_entry_fn
[   89.274222] Call trace:
[   89.276680]  dump_backtrace+0x0/0x2c8
[   89.280348]  show_stack+0x24/0x30
[   89.283671]  dump_stack+0x118/0x19c
[   89.287167]  ubsan_epilogue+0x14/0x60
[   89.290835]  __ubsan_handle_out_of_bounds+0xfc/0x13c
[   89.295828]  MR_LdRaidGet+0x50/0x58 [megaraid_sas]
[   89.300638]  megasas_build_io_fusion+0xbb8/0xd90 [megaraid_sas]
[   89.306576]  megasas_build_and_issue_cmd_fusion+0x138/0x460 [megaraid_sas]
[   89.313468]  megasas_queue_command+0x398/0x3d0 [megaraid_sas]
[   89.319222]  scsi_dispatch_cmd+0x1dc/0x8a8
[   89.323321]  scsi_request_fn+0x8e8/0xdd0
[   89.327249]  __blk_run_queue+0xc4/0x158
[   89.331090]  blk_execute_rq_nowait+0xf4/0x158
[   89.335449]  blk_execute_rq+0xdc/0x158
[   89.339202]  __scsi_execute+0x130/0x258
[   89.343041]  scsi_probe_and_add_lun+0x2fc/0x1488
[   89.347661]  __scsi_scan_target+0x1cc/0x8c8
[   89.351848]  scsi_scan_channel.part.3+0x8c/0xc0
[   89.356382]  scsi_scan_host_selected+0x130/0x1f0
[   89.361002]  do_scsi_scan_host+0xd8/0xf0
[   89.364927]  do_scan_async+0x9c/0x320
[   89.368594]  async_run_entry_fn+0x138/0x420
[   89.372780]  process_one_work+0x61c/0xf08
[   89.376793]  worker_thread+0x13c/0xa70
[   89.380546]  kthread+0x1c8/0x1d0
[   89.383778]  ret_from_fork+0x10/0x1c

This is because when populating Driver Map using firmware raid map, all
non-existing VDs set their ldTgtIdToLd to 0xff, so it can be skipped later.

From drivers/scsi/megaraid/megaraid_sas_base.c ,
memset(instance->ld_ids, 0xff, MEGASAS_MAX_LD_IDS);

From drivers/scsi/megaraid/megaraid_sas_fp.c ,
/* For non existing VDs, iterate to next VD*/
if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
	continue;

However, there are a few places that failed to skip those non-existing VDs
due to off-by-one errors. Then, those 0xff leaked into MR_LdRaidGet(0xff,
map) and triggered the out-of-bound accesses.

Fixes: 51087a8617fe ("megaraid_sas : Extended VD support")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>







scsi: smartpqi: correct lun reset issues
2019-01-26T08:38:35+00:00

Kevin Barnett
kevin.barnett@microsemi.com

2018-12-07T22:29:51+00:00

1da52f241f5251225f1594af2a2af3f3f792263d

[ Upstream commit 2ba55c9851d74eb015a554ef69ddf2ef061d5780 ]

Problem:
The Linux kernel takes a logical volume offline after a LUN reset.  This is
generally accompanied by this message in the dmesg output:

Device offlined - not ready after error recovery

Root Cause:
The root cause is a "quirk" in the timeout handling in the Linux SCSI
layer. The Linux kernel places a 30-second timeout on most media access
commands (reads and writes) that it send to device drivers.  When a media
access command times out, the Linux kernel goes into error recovery mode
for the LUN that was the target of the command that timed out. Every
command that timed out is kept on a list inside of the Linux kernel to be
retried later. The kernel attempts to recover the command(s) that timed out
by issuing a LUN reset followed by a TEST UNIT READY. If the LUN reset and
TEST UNIT READY commands are successful, the kernel retries the command(s)
that timed out.

Each SCSI command issued by the kernel has a result field associated with
it. This field indicates the final result of the command (success or
error). When a command times out, the kernel places a value in this result
field indicating that the command timed out.

The "quirk" is that after the LUN reset and TEST UNIT READY commands are
completed, the kernel checks each command on the timed-out command list
before retrying it. If the result field is still "timed out", the kernel
treats that command as not having been successfully recovered for a
retry. If the number of commands that are in this state are greater than
two, the kernel takes the LUN offline.

Fix:
When our RAIDStack receives a LUN reset, it simply waits until all
outstanding commands complete. Generally, all of these outstanding commands
complete successfully. Therefore, the fix in the smartpqi driver is to
always set the command result field to indicate success when a request
completes successfully. This normally isn’t necessary because the result
field is always initialized to success when the command is submitted to the
driver. So when the command completes successfully, the result field is
left untouched. But in this case, the kernel changes the result field
behind the driver’s back and then expects the field to be changed by the
driver as the commands that timed-out complete.

Reviewed-by: Dave Carroll <david.carroll@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 2ba55c9851d74eb015a554ef69ddf2ef061d5780 ]

Problem:
The Linux kernel takes a logical volume offline after a LUN reset.  This is
generally accompanied by this message in the dmesg output:

Device offlined - not ready after error recovery

Root Cause:
The root cause is a "quirk" in the timeout handling in the Linux SCSI
layer. The Linux kernel places a 30-second timeout on most media access
commands (reads and writes) that it send to device drivers.  When a media
access command times out, the Linux kernel goes into error recovery mode
for the LUN that was the target of the command that timed out. Every
command that timed out is kept on a list inside of the Linux kernel to be
retried later. The kernel attempts to recover the command(s) that timed out
by issuing a LUN reset followed by a TEST UNIT READY. If the LUN reset and
TEST UNIT READY commands are successful, the kernel retries the command(s)
that timed out.

Each SCSI command issued by the kernel has a result field associated with
it. This field indicates the final result of the command (success or
error). When a command times out, the kernel places a value in this result
field indicating that the command timed out.

The "quirk" is that after the LUN reset and TEST UNIT READY commands are
completed, the kernel checks each command on the timed-out command list
before retrying it. If the result field is still "timed out", the kernel
treats that command as not having been successfully recovered for a
retry. If the number of commands that are in this state are greater than
two, the kernel takes the LUN offline.

Fix:
When our RAIDStack receives a LUN reset, it simply waits until all
outstanding commands complete. Generally, all of these outstanding commands
complete successfully. Therefore, the fix in the smartpqi driver is to
always set the command result field to indicate success when a request
completes successfully. This normally isn’t necessary because the result
field is always initialized to success when the command is submitted to the
driver. So when the command completes successfully, the result field is
left untouched. But in this case, the kernel changes the result field
behind the driver’s back and then expects the field to be changed by the
driver as the commands that timed-out complete.

Reviewed-by: Dave Carroll <david.carroll@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>







sysfs: Disable lockdep for driver bind/unbind files
2019-01-26T08:38:35+00:00

Daniel Vetter
daniel.vetter@ffwll.ch

2018-12-19T12:39:09+00:00

54e6f64efc14213c2e76ea063645392a955b67e4

[ Upstream commit 4f4b374332ec0ae9c738ff8ec9bed5cd97ff9adc ]

This is the much more correct fix for my earlier attempt at:

https://lkml.org/lkml/2018/12/10/118

Short recap:

- There's not actually a locking issue, it's just lockdep being a bit
  too eager to complain about a possible deadlock.

- Contrary to what I claimed the real problem is recursion on
  kn->count. Greg pointed me at sysfs_break_active_protection(), used
  by the scsi subsystem to allow a sysfs file to unbind itself. That
  would be a real deadlock, which isn't what's happening here. Also,
  breaking the active protection means we'd need to manually handle
  all the lifetime fun.

- With Rafael we discussed the task_work approach, which kinda works,
  but has two downsides: It's a functional change for a lockdep
  annotation issue, and it won't work for the bind file (which needs
  to get the errno from the driver load function back to userspace).

- Greg also asked why this never showed up: To hit this you need to
  unregister a 2nd driver from the unload code of your first driver. I
  guess only gpus do that. The bug has always been there, but only
  with a recent patch series did we add more locks so that lockdep
  built a chain from unbinding the snd-hda driver to the
  acpi_video_unregister call.

Full lockdep splat:

[12301.898799] ============================================
[12301.898805] WARNING: possible recursive locking detected
[12301.898811] 4.20.0-rc7+ #84 Not tainted
[12301.898815] --------------------------------------------
[12301.898821] bash/5297 is trying to acquire lock:
[12301.898826] 00000000f61c6093 (kn->count#39){++++}, at: kernfs_remove_by_name_ns+0x3b/0x80
[12301.898841] but task is already holding lock:
[12301.898847] 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898856] other info that might help us debug this:
[12301.898862]  Possible unsafe locking scenario:
[12301.898867]        CPU0
[12301.898870]        ----
[12301.898874]   lock(kn->count#39);
[12301.898879]   lock(kn->count#39);
[12301.898883] *** DEADLOCK ***
[12301.898891]  May be due to missing lock nesting notation
[12301.898899] 5 locks held by bash/5297:
[12301.898903]  #0: 00000000cd800e54 (sb_writers#4){.+.+}, at: vfs_write+0x17f/0x1b0
[12301.898915]  #1: 000000000465e7c2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xd3/0x190
[12301.898925]  #2: 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898936]  #3: 00000000414ef7ac (&dev->mutex){....}, at: device_release_driver_internal+0x34/0x240
[12301.898950]  #4: 000000003218fbdf (register_count_mutex){+.+.}, at: acpi_video_unregister+0xe/0x40
[12301.898960] stack backtrace:
[12301.898968] CPU: 1 PID: 5297 Comm: bash Not tainted 4.20.0-rc7+ #84
[12301.898974] Hardware name: Hewlett-Packard HP EliteBook 8460p/161C, BIOS 68SCF Ver. F.01 03/11/2011
[12301.898982] Call Trace:
[12301.898989]  dump_stack+0x67/0x9b
[12301.898997]  __lock_acquire+0x6ad/0x1410
[12301.899003]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899010]  ? find_held_lock+0x2d/0x90
[12301.899017]  ? mutex_spin_on_owner+0xe4/0x150
[12301.899023]  ? find_held_lock+0x2d/0x90
[12301.899030]  ? lock_acquire+0x90/0x180
[12301.899036]  lock_acquire+0x90/0x180
[12301.899042]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899049]  __kernfs_remove+0x296/0x310
[12301.899055]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899060]  ? kernfs_name_hash+0xd/0x80
[12301.899066]  ? kernfs_find_ns+0x6c/0x100
[12301.899073]  kernfs_remove_by_name_ns+0x3b/0x80
[12301.899080]  bus_remove_driver+0x92/0xa0
[12301.899085]  acpi_video_unregister+0x24/0x40
[12301.899127]  i915_driver_unload+0x42/0x130 [i915]
[12301.899160]  i915_pci_remove+0x19/0x30 [i915]
[12301.899169]  pci_device_remove+0x36/0xb0
[12301.899176]  device_release_driver_internal+0x185/0x240
[12301.899183]  unbind_store+0xaf/0x180
[12301.899189]  kernfs_fop_write+0x104/0x190
[12301.899195]  __vfs_write+0x31/0x180
[12301.899203]  ? rcu_read_lock_sched_held+0x6f/0x80
[12301.899209]  ? rcu_sync_lockdep_assert+0x29/0x50
[12301.899216]  ? __sb_start_write+0x13c/0x1a0
[12301.899221]  ? vfs_write+0x17f/0x1b0
[12301.899227]  vfs_write+0xb9/0x1b0
[12301.899233]  ksys_write+0x50/0xc0
[12301.899239]  do_syscall_64+0x4b/0x180
[12301.899247]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[12301.899253] RIP: 0033:0x7f452ac7f7a4
[12301.899259] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 aa f0 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[12301.899273] RSP: 002b:00007ffceafa6918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[12301.899282] RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f452ac7f7a4
[12301.899288] RDX: 000000000000000d RSI: 00005612a1abf7c0 RDI: 0000000000000001
[12301.899295] RBP: 00005612a1abf7c0 R08: 000000000000000a R09: 00005612a1c46730
[12301.899301] R10: 000000000000000a R11: 0000000000000246 R12: 000000000000000d
[12301.899308] R13: 0000000000000001 R14: 00007f452af4a740 R15: 000000000000000d

Looking around I've noticed that usb and i2c already handle similar
recursion problems, where a sysfs file can unbind the same type of
sysfs somewhere else in the hierarchy. Relevant commits are:

commit 356c05d58af05d582e634b54b40050c73609617b
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon May 14 13:30:03 2012 -0400

    sysfs: get rid of some lockdep false positives

commit e9b526fe704812364bca07edd15eadeba163ebfb
Author: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Date:   Fri May 17 14:56:35 2013 +0200

    i2c: suppress lockdep warning on delete_device

Implement the same trick for driver bind/unbind.

v2: Put the macro into bus.c (Greg).

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Arend van Spriel <aspriel@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Vivek Gautam <vivek.gautam@codeaurora.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 4f4b374332ec0ae9c738ff8ec9bed5cd97ff9adc ]

This is the much more correct fix for my earlier attempt at:

https://lkml.org/lkml/2018/12/10/118

Short recap:

- There's not actually a locking issue, it's just lockdep being a bit
  too eager to complain about a possible deadlock.

- Contrary to what I claimed the real problem is recursion on
  kn->count. Greg pointed me at sysfs_break_active_protection(), used
  by the scsi subsystem to allow a sysfs file to unbind itself. That
  would be a real deadlock, which isn't what's happening here. Also,
  breaking the active protection means we'd need to manually handle
  all the lifetime fun.

- With Rafael we discussed the task_work approach, which kinda works,
  but has two downsides: It's a functional change for a lockdep
  annotation issue, and it won't work for the bind file (which needs
  to get the errno from the driver load function back to userspace).

- Greg also asked why this never showed up: To hit this you need to
  unregister a 2nd driver from the unload code of your first driver. I
  guess only gpus do that. The bug has always been there, but only
  with a recent patch series did we add more locks so that lockdep
  built a chain from unbinding the snd-hda driver to the
  acpi_video_unregister call.

Full lockdep splat:

[12301.898799] ============================================
[12301.898805] WARNING: possible recursive locking detected
[12301.898811] 4.20.0-rc7+ #84 Not tainted
[12301.898815] --------------------------------------------
[12301.898821] bash/5297 is trying to acquire lock:
[12301.898826] 00000000f61c6093 (kn->count#39){++++}, at: kernfs_remove_by_name_ns+0x3b/0x80
[12301.898841] but task is already holding lock:
[12301.898847] 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898856] other info that might help us debug this:
[12301.898862]  Possible unsafe locking scenario:
[12301.898867]        CPU0
[12301.898870]        ----
[12301.898874]   lock(kn->count#39);
[12301.898879]   lock(kn->count#39);
[12301.898883] *** DEADLOCK ***
[12301.898891]  May be due to missing lock nesting notation
[12301.898899] 5 locks held by bash/5297:
[12301.898903]  #0: 00000000cd800e54 (sb_writers#4){.+.+}, at: vfs_write+0x17f/0x1b0
[12301.898915]  #1: 000000000465e7c2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xd3/0x190
[12301.898925]  #2: 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898936]  #3: 00000000414ef7ac (&dev->mutex){....}, at: device_release_driver_internal+0x34/0x240
[12301.898950]  #4: 000000003218fbdf (register_count_mutex){+.+.}, at: acpi_video_unregister+0xe/0x40
[12301.898960] stack backtrace:
[12301.898968] CPU: 1 PID: 5297 Comm: bash Not tainted 4.20.0-rc7+ #84
[12301.898974] Hardware name: Hewlett-Packard HP EliteBook 8460p/161C, BIOS 68SCF Ver. F.01 03/11/2011
[12301.898982] Call Trace:
[12301.898989]  dump_stack+0x67/0x9b
[12301.898997]  __lock_acquire+0x6ad/0x1410
[12301.899003]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899010]  ? find_held_lock+0x2d/0x90
[12301.899017]  ? mutex_spin_on_owner+0xe4/0x150
[12301.899023]  ? find_held_lock+0x2d/0x90
[12301.899030]  ? lock_acquire+0x90/0x180
[12301.899036]  lock_acquire+0x90/0x180
[12301.899042]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899049]  __kernfs_remove+0x296/0x310
[12301.899055]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899060]  ? kernfs_name_hash+0xd/0x80
[12301.899066]  ? kernfs_find_ns+0x6c/0x100
[12301.899073]  kernfs_remove_by_name_ns+0x3b/0x80
[12301.899080]  bus_remove_driver+0x92/0xa0
[12301.899085]  acpi_video_unregister+0x24/0x40
[12301.899127]  i915_driver_unload+0x42/0x130 [i915]
[12301.899160]  i915_pci_remove+0x19/0x30 [i915]
[12301.899169]  pci_device_remove+0x36/0xb0
[12301.899176]  device_release_driver_internal+0x185/0x240
[12301.899183]  unbind_store+0xaf/0x180
[12301.899189]  kernfs_fop_write+0x104/0x190
[12301.899195]  __vfs_write+0x31/0x180
[12301.899203]  ? rcu_read_lock_sched_held+0x6f/0x80
[12301.899209]  ? rcu_sync_lockdep_assert+0x29/0x50
[12301.899216]  ? __sb_start_write+0x13c/0x1a0
[12301.899221]  ? vfs_write+0x17f/0x1b0
[12301.899227]  vfs_write+0xb9/0x1b0
[12301.899233]  ksys_write+0x50/0xc0
[12301.899239]  do_syscall_64+0x4b/0x180
[12301.899247]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[12301.899253] RIP: 0033:0x7f452ac7f7a4
[12301.899259] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 aa f0 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[12301.899273] RSP: 002b:00007ffceafa6918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[12301.899282] RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f452ac7f7a4
[12301.899288] RDX: 000000000000000d RSI: 00005612a1abf7c0 RDI: 0000000000000001
[12301.899295] RBP: 00005612a1abf7c0 R08: 000000000000000a R09: 00005612a1c46730
[12301.899301] R10: 000000000000000a R11: 0000000000000246 R12: 000000000000000d
[12301.899308] R13: 0000000000000001 R14: 00007f452af4a740 R15: 000000000000000d

Looking around I've noticed that usb and i2c already handle similar
recursion problems, where a sysfs file can unbind the same type of
sysfs somewhere else in the hierarchy. Relevant commits are:

commit 356c05d58af05d582e634b54b40050c73609617b
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon May 14 13:30:03 2012 -0400

    sysfs: get rid of some lockdep false positives

commit e9b526fe704812364bca07edd15eadeba163ebfb
Author: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Date:   Fri May 17 14:56:35 2013 +0200

    i2c: suppress lockdep warning on delete_device

Implement the same trick for driver bind/unbind.

v2: Put the macro into bus.c (Greg).

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Arend van Spriel <aspriel@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Vivek Gautam <vivek.gautam@codeaurora.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>







ALSA: bebob: fix model-id of unit for Apogee Ensemble
2019-01-26T08:38:35+00:00

Takashi Sakamoto
o-takashi@sakamocchi.jp

2018-12-19T11:00:42+00:00

d9c8a99f35c343b7ba7543ebe367df5f0b4e289f

[ Upstream commit 644b2e97405b0b74845e1d3c2b4fe4c34858062b ]

This commit fixes hard-coded model-id for an unit of Apogee Ensemble with
a correct value. This unit uses DM1500 ASIC produced ArchWave AG (formerly
known as BridgeCo AG).

I note that this model supports three modes in the number of data channels
in tx/rx streams; 8 ch pairs, 10 ch pairs, 18 ch pairs. The mode is
switched by Vendor-dependent AV/C command, like:

$ cd linux-firewire-utils
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0600000000 (8ch pairs)
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0601000000 (10ch pairs)
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0602000000 (18ch pairs)

When switching between different mode, the unit disappears from IEEE 1394
bus, then appears on the bus with different combination of stream formats.
In a mode of 18 ch pairs, available sampling rate is up to 96.0 kHz, else
up to 192.0 kHz.

$ ./hinawa-config-rom-printer /dev/fw1
{ 'bus-info': { 'adj': False,
                'bmc': True,
                'chip_ID': 21474898341,
                'cmc': True,
                'cyc_clk_acc': 100,
                'generation': 2,
                'imc': True,
                'isc': True,
                'link_spd': 2,
                'max_ROM': 1,
                'max_rec': 512,
                'name': '1394',
                'node_vendor_ID': 987,
                'pmc': False},
  'root-directory': [ ['HARDWARE_VERSION', 19],
                      [ 'NODE_CAPABILITIES',
                        { 'addressing': {'64': True, 'fix': True, 'prv': False},
                          'misc': {'int': False, 'ms': False, 'spt': True},
                          'state': { 'atn': False,
                                     'ded': False,
                                     'drq': True,
                                     'elo': False,
                                     'init': False,
                                     'lst': True,
                                     'off': False},
                          'testing': {'bas': False, 'ext': False}}],
                      ['VENDOR', 987],
                      ['DESCRIPTOR', 'Apogee Electronics'],
                      ['MODEL', 126702],
                      ['DESCRIPTOR', 'Ensemble'],
                      ['VERSION', 5297],
                      [ 'UNIT',
                        [ ['SPECIFIER_ID', 41005],
                          ['VERSION', 65537],
                          ['MODEL', 126702],
                          ['DESCRIPTOR', 'Ensemble']]],
                      [ 'DEPENDENT_INFO',
                        [ ['SPECIFIER_ID', 2037],
                          ['VERSION', 1],
                          [(58, 'IMMEDIATE'), 16777159],
                          [(59, 'IMMEDIATE'), 1048576],
                          [(60, 'IMMEDIATE'), 16777159],
                          [(61, 'IMMEDIATE'), 6291456]]]]}

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>





[ Upstream commit 644b2e97405b0b74845e1d3c2b4fe4c34858062b ]

This commit fixes hard-coded model-id for an unit of Apogee Ensemble with
a correct value. This unit uses DM1500 ASIC produced ArchWave AG (formerly
known as BridgeCo AG).

I note that this model supports three modes in the number of data channels
in tx/rx streams; 8 ch pairs, 10 ch pairs, 18 ch pairs. The mode is
switched by Vendor-dependent AV/C command, like:

$ cd linux-firewire-utils
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0600000000 (8ch pairs)
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0601000000 (10ch pairs)
$ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0602000000 (18ch pairs)

When switching between different mode, the unit disappears from IEEE 1394
bus, then appears on the bus with different combination of stream formats.
In a mode of 18 ch pairs, available sampling rate is up to 96.0 kHz, else
up to 192.0 kHz.

$ ./hinawa-config-rom-printer /dev/fw1
{ 'bus-info': { 'adj': False,
                'bmc': True,
                'chip_ID': 21474898341,
                'cmc': True,
                'cyc_clk_acc': 100,
                'generation': 2,
                'imc': True,
                'isc': True,
                'link_spd': 2,
                'max_ROM': 1,
                'max_rec': 512,
                'name': '1394',
                'node_vendor_ID': 987,
                'pmc': False},
  'root-directory': [ ['HARDWARE_VERSION', 19],
                      [ 'NODE_CAPABILITIES',
                        { 'addressing': {'64': True, 'fix': True, 'prv': False},
                          'misc': {'int': False, 'ms': False, 'spt': True},
                          'state': { 'atn': False,
                                     'ded': False,
                                     'drq': True,
                                     'elo': False,
                                     'init': False,
                                     'lst': True,
                                     'off': False},
                          'testing': {'bas': False, 'ext': False}}],
                      ['VENDOR', 987],
                      ['DESCRIPTOR', 'Apogee Electronics'],
                      ['MODEL', 126702],
                      ['DESCRIPTOR', 'Ensemble'],
                      ['VERSION', 5297],
                      [ 'UNIT',
                        [ ['SPECIFIER_ID', 41005],
                          ['VERSION', 65537],
                          ['MODEL', 126702],
                          ['DESCRIPTOR', 'Ensemble']]],
                      [ 'DEPENDENT_INFO',
                        [ ['SPECIFIER_ID', 2037],
                          ['VERSION', 1],
                          [(58, 'IMMEDIATE'), 16777159],
                          [(59, 'IMMEDIATE'), 1048576],
                          [(60, 'IMMEDIATE'), 16777159],
                          [(61, 'IMMEDIATE'), 6291456]]]]}

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>