Commit graph

932869 commits

Author SHA1 Message Date
Zhenyu Wang
40dcee1b7c drm/i915/gvt: move workload destroy out of execlist complete
To let execlist.c only handle execlist handling and keep other
workload cleanup function in scheduler.c to align with other
workload specific handling there. This doesn't change current
code behavior.

Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200506094318.105604-1-zhenyuw@linux.intel.com
2020-05-08 12:34:12 +08:00
Roberto Sassu
0c4395fb2a evm: Fix possible memory leak in evm_calc_hmac_or_hash()
Don't immediately return if the signature is portable and security.ima is
not present. Just set error so that memory allocated is freed before
returning from evm_calc_hmac_or_hash().

Fixes: 50b977481f ("EVM: Add support for portable signature format")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 23:36:25 -04:00
Dave Airlie
c61b0b97ef Merge tag 'amd-drm-fixes-5.7-2020-05-06' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
amd-drm-fixes-5.7-2020-05-06:

amdgpu:
- Runtime PM fixes
- DC fix for PPC
- Misc DC fixes

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506212257.3893-1-alexander.deucher@amd.com
2020-05-08 13:31:39 +10:00
Dave Airlie
370fb6b0aa Merge tag 'amd-drm-next-5.8-2020-04-30' of git://people.freedesktop.org/~agd5f/linux into drm-next
amd-drm-next-5.8-2020-04-30:

amdgpu:
- SR-IOV fixes
- SDMA fix for Navi
- VCN 2.5 DPG fixes
- Display fixes
- Display stuttering fixes for pageflip and cursor
- Add support for handling encrypted GPU memory
- Add UAPI for encrypted GPU memory
- Rework IB pool handling

amdkfd:
- Expose asic revision in topology
- Add UAPI for GWS (Global Wave Sync) resource management

UAPI:
- Add amdgpu UAPI for encrypted GPU memory
  Used by: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4401
- Add amdkfd UAPI for GWS (Global Wave Sync) resource management
  Thunk usage of KFD ioctl: https://github.com/RadeonOpenCompute/ROCT-Thunk-Interface/blob/roc-2.8.0/src/queues.c#L840
  ROCr usage of Thunk API: https://github.com/RadeonOpenCompute/ROCR-Runtime/blob/roc-3.1.0/src/core/runtime/amd_gpu_agent.cpp#L597
  HCC code using ROCr API: 98ee9f3494/lib/hsa/mcwamp_hsa.cpp (L2161)
  HIP code using HCC API: cf8589b8c8/src/hip_module.cpp (L567)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430212951.3902-1-alexander.deucher@amd.com
2020-05-08 13:31:08 +10:00
Michael Ellerman
e2a8b49e79 powerpc/uaccess: Don't use "m<>" constraint
The "m<>" constraint breaks compilation with GCC 4.6.x era compilers.

The use of the constraint allows the compiler to use update-form
instructions, however in practice current compilers never generate
those forms for any of the current uses of __put_user_asm_goto().

We anticipate that GCC 4.6 will be declared unsupported for building
the kernel in the not too distant future. So for now just switch to
the "m" constraint.

Fixes: 334710b149 ("powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Link: https://lore.kernel.org/r/20200507123324.2250024-1-mpe@ellerman.id.au
2020-05-08 13:30:42 +10:00
Krzysztof Struczynski
b59fda449c ima: Set again build_ima_appraise variable
After adding the new add_rule() function in commit c52657d93b
("ima: refactor ima_init_policy()"), all appraisal flags are added to the
temp_ima_appraise variable. Revert to the previous behavior instead of
removing build_ima_appraise, to benefit from the protection offered by
__ro_after_init.

The mentioned commit introduced a bug, as it makes all the flags
modifiable, while build_ima_appraise flags can be protected with
__ro_after_init.

Cc: stable@vger.kernel.org # 5.0.x
Fixes: c52657d93b ("ima: refactor ima_init_policy()")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:09 -04:00
Krzysztof Struczynski
6ee28442a4 ima: Remove redundant policy rule set in add_rules()
Function ima_appraise_flag() returns the flag to be set in
temp_ima_appraise depending on the hook identifier passed as an argument.
It is not necessary to set the flag again for the POLICY_CHECK hook.

Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:08 -04:00
Krzysztof Struczynski
1129d31b55 ima: Fix ima digest hash table key calculation
Function hash_long() accepts unsigned long, while currently only one byte
is passed from ima_hash_key(), which calculates a key for ima_htable.

Given that hashing the digest does not give clear benefits compared to
using the digest itself, remove hash_long() and return the modulus
calculated on the first two bytes of the digest with the number of slots.
Also reduce the depth of the hash table by doubling the number of slots.

Cc: stable@vger.kernel.org
Fixes: 3323eec921 ("integrity: IMA as an integrity service provider")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Acked-by: David.Laight@aculab.com (big endian system concerns)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:07 -04:00
Gustavo A. R. Silva
0090c1edeb audit: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-07 22:49:28 -04:00
Dick Kennedy
29022b6130 scsi: lpfc: Update lpfc version to 12.8.0.1
Update lpfc version to 12.8.0.1

Link: https://lore.kernel.org/r/20200501214310.91713-10-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:27 -04:00
Dick Kennedy
8cdc5a223e scsi: lpfc: Fix MDS Diagnostic Enablement definition
The MDS diagnostic enablement bit for the adapter interface is incorrect in
the driver header.

Correct the bit position for the SET_FEATURE MDS bit.

Link: https://lore.kernel.org/r/20200501214310.91713-9-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:26 -04:00
Dick Kennedy
a7fc071ab5 scsi: lpfc: Fix noderef and address space warnings
Running make C=1 M=drivers/scsi/lpfc triggers sparse warnings

Correct the code generating the following errors:

 - Incompatible address space assignment without proper conversion.

 - Deference of usespace and per-cpu pointers.

Link: https://lore.kernel.org/r/20200501214310.91713-8-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:26 -04:00
Dick Kennedy
88acb4d9ff scsi: lpfc: Remove unnecessary lockdep_assert_held calls
In an audit of lockdep calls in the driver, there are multiple lockdep
checks in successive calling layers. E.g. a routine checks, and then calls
a lower routine that also checks, and so on. Calling sequences result in
many redundant checks.

Refine the code to remove lower-level lockdep checks.  Update comments on
the lock, correcting a few places where lock object in comment was
incorrect.

Link: https://lore.kernel.org/r/20200501214310.91713-7-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:24 -04:00
Dick Kennedy
3048e3e805 scsi: lpfc: Change default queue allocation for reduced memory consumption
By default, the driver attempts to allocate a hdwq per logical cpu in order
to provide good cpu affinity. Some systems have extremely high cpu counts
and this can significantly raise memory consumption.

In testing on x86 platforms (non-AMD) it is found that sharing of a hdwq by
a physical cpu and its HT cpu can occur with little performance
degredation. By sharing, the hdwq count can be halved, significantly
reducing the memory overhead.

Change the default behavior of the driver on non-AMD x86 platforms to
share a hdwq by the cpu and its HT cpu.

Link: https://lore.kernel.org/r/20200501214310.91713-6-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:24 -04:00
Dick Kennedy
f809da6db6 scsi: lpfc: Fix negation of else clause in lpfc_prep_node_fc4type
Implementation of a previous patch added a condition to an if check that
always end up with the if test being true. Execution of the else clause was
inadvertently negated.  The additional condition check was incorrect and
unnecessary after the other modifications had been done in that patch.

Remove the check from the if series.

Link: https://lore.kernel.org/r/20200501214310.91713-5-jsmart2021@gmail.com
Fixes: b95b21193c ("scsi: lpfc: Fix loss of remote port after devloss due to lack of RPIs")
Cc: <stable@vger.kernel.org> # v5.4+
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:22 -04:00
Dick Kennedy
b98214f607 scsi: lpfc: Remove re-binding of nvme rport during registration
The lldd rebinds the ndlp with rport during a nvme rport registration (via
nvme_fc_register_remoteport). If rport & ndlp pointers are same as the
previous one, the lldd will re-use the ndlp and rport association without
re-initialization. This assumption is incorrect. The lldd should be
ignorant of whether the returned rport pointer is new or not, and should
always assume it is new.

Remove the re-binding code, always assumes that rport pointer received from
transport is a new pointer.

Link: https://lore.kernel.org/r/20200501214310.91713-4-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:21 -04:00
Dick Kennedy
164ba8d2df scsi: lpfc: Maintain atomic consistency of queue_claimed flag
A previous change introduced the atomic use of queue_claimed flag for eq's
and cq's.  The code works fine, but the clearing of the queue_claimed flag
is not atomic.

Change queue_claimed = 0 into xchg(&queue_claimed, 0) to be consistent for
change under atomicity.

Link: https://lore.kernel.org/r/20200501214310.91713-3-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:47:21 -04:00
Linus Torvalds
79dede78c0 Merge branch 'for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem fix from James Morris:
 "Fix the default value of fs_context_parse_param hook"

* 'for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  security: Fix the default value of fs_context_parse_param hook
2020-05-07 19:43:13 -07:00
Bodo Stroesser
356ba2a8bc scsi: target: tcmu: Make pgr_support and alua_support attributes writable
Currently in tcmu reservation commands are handled by core's pr
implementation (default) or completely rejected (emulate_pr set to 0). We
additionally want to be able to do full reservation handling in
userspace. Therefore we need a way to set TRANSPORT_FLAG_PASSTHROUGH_PGR.

The inverted flag is displayed by attribute pgr_support.  Since we moved
the flag from transport/backend to se_device in the previous commit, we now
can make it changeable per device by allowing to write the attribute.  The
new field transport_flags_changeable in transport/backend is used to reject
writing if not allowed for a backend.

Regarding ALUA we also want to be able to passthrough commands to userspace
in tcmu. Therefore we need TRANSPORT_FLAG_PASSTHROUGH_ALUA to be
changeable, because by setting it we can switch off all ALUA checks in
core. So we also set TRANSPORT_FLAG_PASSTHROUGH_ALUA in tcmu's
transport_flags_changeable.

Of course, ALUA and reservation handling in userspace will work only, if
session/nexus information is sent to userspace along with every
command. This will be object of a patch series announced by Mike Christie.

Link: https://lore.kernel.org/r/20200427150823.15350-5-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:39:22 -04:00
Bodo Stroesser
69088a0494 scsi: target: Make transport_flags per device
pgr_support and alua_support device attributes show the inverted value of
the transport_flags:

 * TRANSPORT_FLAG_PASSTHROUGH_PGR
 * TRANSPORT_FLAG_PASSTHROUGH_ALUA

These attributes are per device, while the flags are per backend. Rename
the transport_flags in backend/transport to transport_flags_default and use
this value to initialize the new transport_flags field in the se_device
structure.

Now data and attribute both are per se_device.

Link: https://lore.kernel.org/r/20200427150823.15350-4-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:39:21 -04:00
Bodo Stroesser
4703b6252b scsi: target: tcmu: Add attributes enforce_pr_isids and force_pr_aptpl
tcmu has not set TRANSPORT_FLAG_PASSTHROUGH_PGR. Therefore the in-core pr
emulation is active by default, but there are some attributes for
configuration missing. Add them.

Link: https://lore.kernel.org/r/20200427150823.15350-3-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:39:18 -04:00
Bodo Stroesser
9299941716 scsi: target: Add missing emulate_pr attribute to passthrough backends
In commit b49d6f7885 ("scsi: target: add emulate_pr backstore attr to
toggle PR support") the new attribute emulate_pr was added.

passthrough_parse_cdb() uses the attribute's value to distinguish whether
reservation commands should be rejected or not.  But the new attribute was
not added to passthrough_attrib_attrs, so in pscsi and tcmu - the users of
passthrough_parse_cdb() - the attribute is not available to change parser's
behavior.

Link: https://lore.kernel.org/r/20200427150823.15350-2-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:39:17 -04:00
Sreekanth Reddy
e869f8ea6a scsi: mpt3sas: Disable DIF when prot_mask set to zero
By default DIF Type 1, DIF Type 2 & DIF Type 3 will be enabled.  Also,
users can enable either DIF Type 1 or DIF Type 2 or DIF Type 3 or in any
combination using the prot_mask module parameter.

However, when the user provides a prot_mask module parameter value of zero,
then the driver is not disabling the DIF. Instead it enables all three
types.

Modify the driver to disable the DIF support if the user provides a
prot_mask module parameter value of zero.

Link: https://lore.kernel.org/r/1588065902-2726-1-git-send-email-sreekanth.reddy@broadcom.com
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:29:31 -04:00
Henry Willard
14f69140ff mm: limit boost_watermark on small zones
Commit 1c30844d2d ("mm: reclaim small amounts of memory when an
external fragmentation event occurs") adds a boost_watermark() function
which increases the min watermark in a zone by at least
pageblock_nr_pages or the number of pages in a page block.

On Arm64, with 64K pages and 512M huge pages, this is 8192 pages or
512M.  It does this regardless of the number of managed pages managed in
the zone or the likelihood of success.

This can put the zone immediately under water in terms of allocating
pages from the zone, and can cause a small machine to fail immediately
due to OoM.  Unlike set_recommended_min_free_kbytes(), which
substantially increases min_free_kbytes and is tied to THP,
boost_watermark() can be called even if THP is not active.

The problem is most likely to appear on architectures such as Arm64
where pageblock_nr_pages is very large.

It is desirable to run the kdump capture kernel in as small a space as
possible to avoid wasting memory.  In some architectures, such as Arm64,
there are restrictions on where the capture kernel can run, and
therefore, the space available.  A capture kernel running in 768M can
fail due to OoM immediately after boost_watermark() sets the min in zone
DMA32, where most of the memory is, to 512M.  It fails even though there
is over 500M of free memory.  With boost_watermark() suppressed, the
capture kernel can run successfully in 448M.

This patch limits boost_watermark() to boosting a zone's min watermark
only when there are enough pages that the boost will produce positive
results.  In this case that is estimated to be four times as many pages
as pageblock_nr_pages.

Mel said:

: There is no harm in marking it stable.  Clearly it does not happen very
: often but it's not impossible.  32-bit x86 is a lot less common now
: which would previously have been vulnerable to triggering this easily.
: ppc64 has a larger base page size but typically only has one zone.
: arm64 is likely the most vulnerable, particularly when CMA is
: configured with a small movable zone.

Fixes: 1c30844d2d ("mm: reclaim small amounts of memory when an external fragmentation event occurs")
Signed-off-by: Henry Willard <henry.willard@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1588294148-6586-1-git-send-email-henry.willard@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Kees Cook
8d58f222e8 ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST
The documentation for UBSAN_ALIGNMENT already mentions that it should
not be used on all*config builds (and for efficient-unaligned-access
architectures), so just refactor the Kconfig to correctly implement this
so randconfigs will stop creating insane images that freak out objtool
under CONFIG_UBSAN_TRAP (due to the false positives producing functions
that never return, etc).

Link: http://lkml.kernel.org/r/202005011433.C42EA3E2D@keescook
Fixes: 0887a7ebc9 ("ubsan: add trap instrumentation option")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
  Link: https://lore.kernel.org/linux-next/202004231224.D6B3B650@keescook/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Qiwu Chen
17e34526f0 mm/vmscan: remove unnecessary argument description of isolate_lru_pages()
Since commit a9e7c39fa9 ("mm/vmscan.c: remove 7th argument of
isolate_lru_pages()"), the explanation of 'mode' argument has been
unnecessary.  Let's remove it.

Signed-off-by: Qiwu Chen <chenqiwu@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200501090346.2894-1-chenqiwu@xiaomi.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Roman Penyaev
412895f03c epoll: atomically remove wait entry on wake up
This patch does two things:

 - fixes a lost wakeup introduced by commit 339ddb53d3 ("fs/epoll:
   remove unnecessary wakeups of nested epoll")

 - improves performance for events delivery.

The description of the problem is the following: if N (>1) threads are
waiting on ep->wq for new events and M (>1) events come, it is quite
likely that >1 wakeups hit the same wait queue entry, because there is
quite a big window between __add_wait_queue_exclusive() and the
following __remove_wait_queue() calls in ep_poll() function.

This can lead to lost wakeups, because thread, which was woken up, can
handle not all the events in ->rdllist.  (in better words the problem is
described here: https://lkml.org/lkml/2019/10/7/905)

The idea of the current patch is to use init_wait() instead of
init_waitqueue_entry().

Internally init_wait() sets autoremove_wake_function as a callback,
which removes the wait entry atomically (under the wq locks) from the
list, thus the next coming wakeup hits the next wait entry in the wait
queue, thus preventing lost wakeups.

Problem is very well reproduced by the epoll60 test case [1].

Wait entry removal on wakeup has also performance benefits, because
there is no need to take a ep->lock and remove wait entry from the queue
after the successful wakeup.  Here is the timing output of the epoll60
test case:

  With explicit wakeup from ep_scan_ready_list() (the state of the
  code prior 339ddb53d3):

    real    0m6.970s
    user    0m49.786s
    sys     0m0.113s

 After this patch:

   real    0m5.220s
   user    0m36.879s
   sys     0m0.019s

The other testcase is the stress-epoll [2], where one thread consumes
all the events and other threads produce many events:

  With explicit wakeup from ep_scan_ready_list() (the state of the
  code prior 339ddb53d3):

    threads  events/ms  run-time ms
          8       5427         1474
         16       6163         2596
         32       6824         4689
         64       7060         9064
        128       6991        18309

 After this patch:

    threads  events/ms  run-time ms
          8       5598         1429
         16       7073         2262
         32       7502         4265
         64       7640         8376
        128       7634        16767

 (number of "events/ms" represents event bandwidth, thus higher is
  better; number of "run-time ms" represents overall time spent
  doing the benchmark, thus lower is better)

[1] tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c
[2] https://github.com/rouming/test-tools/blob/master/stress-epoll.c

Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jason Baron <jbaron@akamai.com>
Cc: Khazhismel Kumykov <khazhy@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Heiher <r@hev.cc>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200430130326.1368509-2-rpenyaev@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Roman Penyaev
474328c06e kselftests: introduce new epoll60 testcase for catching lost wakeups
This test case catches lost wake up introduced by commit 339ddb53d3
("fs/epoll: remove unnecessary wakeups of nested epoll")

The test is simple: we have 10 threads and 10 event fds.  Each thread
can harvest only 1 event.  1 producer fires all 10 events at once and
waits that all 10 events will be observed by 10 threads.

In case of lost wakeup epoll_wait() will timeout and 0 will be returned.

Test case catches two sort of problems: forgotten wakeup on event, which
hits the ->ovflist list, this problem was fixed by:

  5a2513239750 ("eventpoll: fix missing wakeup for ovflist in ep_poll_callback")

the other problem is when several sequential events hit the same waiting
thread, thus other waiters get no wakeups.  Problem is fixed in the
following patch.

Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Khazhismel Kumykov <khazhy@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Heiher <r@hev.cc>
Cc: Jason Baron <jbaron@akamai.com>
Link: http://lkml.kernel.org/r/20200430130326.1368509-1-rpenyaev@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Filipe Manana
28307d938f percpu: make pcpu_alloc() aware of current gfp context
Since 5.7-rc1, on btrfs we have a percpu counter initialization for
which we always pass a GFP_KERNEL gfp_t argument (this happens since
commit 2992df7326 ("btrfs: Implement DREW lock")).

That is safe in some contextes but not on others where allowing fs
reclaim could lead to a deadlock because we are either holding some
btrfs lock needed for a transaction commit or holding a btrfs
transaction handle open.  Because of that we surround the call to the
function that initializes the percpu counter with a NOFS context using
memalloc_nofs_save() (this is done at btrfs_init_fs_root()).

However it turns out that this is not enough to prevent a possible
deadlock because percpu_alloc() determines if it is in an atomic context
by looking exclusively at the gfp flags passed to it (GFP_KERNEL in this
case) and it is not aware that a NOFS context is set.

Because percpu_alloc() thinks it is in a non atomic context it locks the
pcpu_alloc_mutex.  This can result in a btrfs deadlock when
pcpu_balance_workfn() is running, has acquired that mutex and is waiting
for reclaim, while the btrfs task that called percpu_counter_init() (and
therefore percpu_alloc()) is holding either the btrfs commit_root
semaphore or a transaction handle (done fs/btrfs/backref.c:
iterate_extent_inodes()), which prevents reclaim from finishing as an
attempt to commit the current btrfs transaction will deadlock.

Lockdep reports this issue with the following trace:

  ======================================================
  WARNING: possible circular locking dependency detected
  5.6.0-rc7-btrfs-next-77 #1 Not tainted
  ------------------------------------------------------
  kswapd0/91 is trying to acquire lock:
  ffff8938a3b3fdc8 (&delayed_node->mutex){+.+.}, at: __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]

  but task is already holding lock:
  ffffffffb4f0dbc0 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #4 (fs_reclaim){+.+.}:
         fs_reclaim_acquire.part.0+0x25/0x30
         __kmalloc+0x5f/0x3a0
         pcpu_create_chunk+0x19/0x230
         pcpu_balance_workfn+0x56a/0x680
         process_one_work+0x235/0x5f0
         worker_thread+0x50/0x3b0
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  -> #3 (pcpu_alloc_mutex){+.+.}:
         __mutex_lock+0xa9/0xaf0
         pcpu_alloc+0x480/0x7c0
         __percpu_counter_init+0x50/0xd0
         btrfs_drew_lock_init+0x22/0x70 [btrfs]
         btrfs_get_fs_root+0x29c/0x5c0 [btrfs]
         resolve_indirect_refs+0x120/0xa30 [btrfs]
         find_parent_nodes+0x50b/0xf30 [btrfs]
         btrfs_find_all_leafs+0x60/0xb0 [btrfs]
         iterate_extent_inodes+0x139/0x2f0 [btrfs]
         iterate_inodes_from_logical+0xa1/0xe0 [btrfs]
         btrfs_ioctl_logical_to_ino+0xb4/0x190 [btrfs]
         btrfs_ioctl+0x165a/0x3130 [btrfs]
         ksys_ioctl+0x87/0xc0
         __x64_sys_ioctl+0x16/0x20
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #2 (&fs_info->commit_root_sem){++++}:
         down_write+0x38/0x70
         btrfs_cache_block_group+0x2ec/0x500 [btrfs]
         find_free_extent+0xc6a/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         commit_cowonly_roots+0x55/0x310 [btrfs]
         btrfs_commit_transaction+0x509/0xb20 [btrfs]
         sync_filesystem+0x74/0x90
         generic_shutdown_super+0x22/0x100
         kill_anon_super+0x14/0x30
         btrfs_kill_super+0x12/0x20 [btrfs]
         deactivate_locked_super+0x31/0x70
         cleanup_mnt+0x100/0x160
         task_work_run+0x93/0xc0
         exit_to_usermode_loop+0xf9/0x100
         do_syscall_64+0x20d/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #1 (&space_info->groups_sem){++++}:
         down_read+0x3c/0x140
         find_free_extent+0xef6/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         btrfs_search_slot+0x50c/0xd60 [btrfs]
         btrfs_lookup_inode+0x3a/0xc0 [btrfs]
         __btrfs_update_delayed_inode+0x90/0x280 [btrfs]
         __btrfs_commit_inode_delayed_items+0x81f/0x870 [btrfs]
         __btrfs_run_delayed_items+0x8e/0x180 [btrfs]
         btrfs_commit_transaction+0x31b/0xb20 [btrfs]
         iterate_supers+0x87/0xf0
         ksys_sync+0x60/0xb0
         __ia32_sys_sync+0xa/0x10
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #0 (&delayed_node->mutex){+.+.}:
         __lock_acquire+0xef0/0x1c80
         lock_acquire+0xa2/0x1d0
         __mutex_lock+0xa9/0xaf0
         __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
         btrfs_evict_inode+0x40d/0x560 [btrfs]
         evict+0xd9/0x1c0
         dispose_list+0x48/0x70
         prune_icache_sb+0x54/0x80
         super_cache_scan+0x124/0x1a0
         do_shrink_slab+0x176/0x440
         shrink_slab+0x23a/0x2c0
         shrink_node+0x188/0x6e0
         balance_pgdat+0x31d/0x7f0
         kswapd+0x238/0x550
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  other info that might help us debug this:

  Chain exists of:
    &delayed_node->mutex --> pcpu_alloc_mutex --> fs_reclaim

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(fs_reclaim);
                                 lock(pcpu_alloc_mutex);
                                 lock(fs_reclaim);
    lock(&delayed_node->mutex);

   *** DEADLOCK ***

  3 locks held by kswapd0/91:
   #0: (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30
   #1: (shrinker_rwsem){++++}, at: shrink_slab+0x12f/0x2c0
   #2: (&type->s_umount_key#43){++++}, at: trylock_super+0x16/0x50

  stack backtrace:
  CPU: 1 PID: 91 Comm: kswapd0 Not tainted 5.6.0-rc7-btrfs-next-77 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x8f/0xd0
   check_noncircular+0x170/0x190
   __lock_acquire+0xef0/0x1c80
   lock_acquire+0xa2/0x1d0
   __mutex_lock+0xa9/0xaf0
   __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
   btrfs_evict_inode+0x40d/0x560 [btrfs]
   evict+0xd9/0x1c0
   dispose_list+0x48/0x70
   prune_icache_sb+0x54/0x80
   super_cache_scan+0x124/0x1a0
   do_shrink_slab+0x176/0x440
   shrink_slab+0x23a/0x2c0
   shrink_node+0x188/0x6e0
   balance_pgdat+0x31d/0x7f0
   kswapd+0x238/0x550
   kthread+0x120/0x140
   ret_from_fork+0x3a/0x50

This could be fixed by making btrfs pass GFP_NOFS instead of GFP_KERNEL
to percpu_counter_init() in contextes where it is not reclaim safe,
however that type of approach is discouraged since
memalloc_[nofs|noio]_save() were introduced.  Therefore this change
makes pcpu_alloc() look up into an existing nofs/noio context before
deciding whether it is in an atomic context or not.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/20200430164356.15543-1-fdmanana@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:21 -07:00
Waiman Long
cbfc35a486 mm/slub: fix incorrect interpretation of s->offset
In a couple of places in the slub memory allocator, the code uses
"s->offset" as a check to see if the free pointer is put right after the
object.  That check is no longer true with commit 3202fa62fb ("slub:
relocate freelist pointer to middle of object").

As a result, echoing "1" into the validate sysfs file, e.g.  of dentry,
may cause a bunch of "Freepointer corrupt" error reports like the
following to appear with the system in panic afterwards.

  =============================================================================
  BUG dentry(666:pmcd.service) (Tainted: G    B): Freepointer corrupt
  -----------------------------------------------------------------------------

To fix it, use the check "s->offset == s->inuse" in the new helper
function freeptr_outside_object() instead.  Also add another helper
function get_info_end() to return the end of info block (inuse + free
pointer if not overlapping with object).

Fixes: 3202fa62fb ("slub: relocate freelist pointer to middle of object")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Vitaly Nikolenko <vnik@duasynt.com>
Cc: Silvio Cesare <silvio.cesare@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Markus Elfring <Markus.Elfring@web.de>
Cc: Changbin Du <changbin.du@gmail.com>
Link: http://lkml.kernel.org/r/20200429135328.26976-1-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Aymeric Agon-Rambosson
50e36be1fb scripts/gdb: repair rb_first() and rb_last()
The current implementations of the rb_first() and rb_last() gdb
functions have a variable that references itself in its instanciation,
which causes the function to throw an error if a specific condition on
the argument is met.  The original author rather intended to reference
the argument and made a typo.  Referring the argument instead makes the
function work as intended.

Signed-off-by: Aymeric Agon-Rambosson <aymeric.agon@yandex.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200427051029.354840-1-aymeric.agon@yandex.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Khazhismel Kumykov
0c54a6a44b eventpoll: fix missing wakeup for ovflist in ep_poll_callback
In the event that we add to ovflist, before commit 339ddb53d3
("fs/epoll: remove unnecessary wakeups of nested epoll") we would be
woken up by ep_scan_ready_list, and did no wakeup in ep_poll_callback.

With that wakeup removed, if we add to ovflist here, we may never wake
up.  Rather than adding back the ep_scan_ready_list wakeup - which was
resulting in unnecessary wakeups, trigger a wake-up in ep_poll_callback.

We noticed that one of our workloads was missing wakeups starting with
339ddb53d3 and upon manual inspection, this wakeup seemed missing to me.
With this patch added, we no longer see missing wakeups.  I haven't yet
tried to make a small reproducer, but the existing kselftests in
filesystem/epoll passed for me with this patch.

[khazhy@google.com: use if/elif instead of goto + cleanup suggested by Roman]
  Link: http://lkml.kernel.org/r/20200424190039.192373-1-khazhy@google.com
Fixes: 339ddb53d3 ("fs/epoll: remove unnecessary wakeups of nested epoll")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Roman Penyaev <rpenyaev@suse.de>
Cc: Heiher <r@hev.cc>
Cc: Jason Baron <jbaron@akamai.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200424025057.118641-1-khazhy@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Janakarajan Natarajan
996ed22c7a arch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory()
When trying to lock read-only pages, sev_pin_memory() fails because
FOLL_WRITE is used as the flag for get_user_pages_fast().

Commit 73b0140bf0 ("mm/gup: change GUP fast to use flags rather than a
write 'bool'") updated the get_user_pages_fast() call sites to use
flags, but incorrectly updated the call in sev_pin_memory().  As the
original coding of this call was correct, revert the change made by that
commit.

Fixes: 73b0140bf0 ("mm/gup: change GUP fast to use flags rather than a write 'bool'")
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Link: http://lkml.kernel.org/r/20200423152419.87202-1-Janakarajan.Natarajan@amd.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Ivan Delalande
e08df079b2 scripts/decodecode: fix trapping instruction formatting
If the trapping instruction contains a ':', for a memory access through
segment registers for example, the sed substitution will insert the '*'
marker in the middle of the instruction instead of the line address:

	2b:   65 48 0f c7 0f          cmpxchg16b %gs:*(%rdi)          <-- trapping instruction

I started to think I had forgotten some quirk of the assembly syntax
before noticing that it was actually coming from the script.  Fix it to
add the address marker at the right place for these instructions:

	28:   49 8b 06                mov    (%r14),%rax
	2b:*  65 48 0f c7 0f          cmpxchg16b %gs:(%rdi)           <-- trapping instruction
	30:   0f 94 c0                sete   %al

Fixes: 18ff44b189 ("scripts/decodecode: make faulting insn ptr more robust")
Signed-off-by: Ivan Delalande <colona@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200419223653.GA31248@visor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Maciej Grochowski
324cfb1956 kernel/kcov.c: fix typos in kcov_remote_start documentation
Signed-off-by: Maciej Grochowski <maciej.grochowski@pm.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Link: http://lkml.kernel.org/r/20200420030259.31674-1-maciek.grochowski@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
David Hildenbrand
e84fe99b68 mm/page_alloc: fix watchdog soft lockups during set_zone_contiguous()
Without CONFIG_PREEMPT, it can happen that we get soft lockups detected,
e.g., while booting up.

  watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-next-20200331+ #4
  Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
  RIP: __pageblock_pfn_to_page+0x134/0x1c0
  Call Trace:
   set_zone_contiguous+0x56/0x70
   page_alloc_init_late+0x166/0x176
   kernel_init_freeable+0xfa/0x255
   kernel_init+0xa/0x106
   ret_from_fork+0x35/0x40

The issue becomes visible when having a lot of memory (e.g., 4TB)
assigned to a single NUMA node - a system that can easily be created
using QEMU.  Inside VMs on a hypervisor with quite some memory
overcommit, this is fairly easy to trigger.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416073417.5003-1-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Yafang Shao
11d6761218 mm, memcg: fix error return value of mem_cgroup_css_alloc()
When I run my memcg testcase which creates lots of memcgs, I found
there're unexpected out of memory logs while there're still enough
available free memory.  The error log is

  mkdir: cannot create directory 'foo.65533': Cannot allocate memory

The reason is when we try to create more than MEM_CGROUP_ID_MAX memcgs,
an -ENOMEM errno will be set by mem_cgroup_css_alloc(), but the right
errno should be -ENOSPC "No space left on device", which is an
appropriate errno for userspace's failed mkdir.

As the errno really misled me, we should make it right.  After this
patch, the error log will be

  mkdir: cannot create directory 'foo.65533': No space left on device

[akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal]
[akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal]
Fixes: 73f576c04b ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Link: http://lkml.kernel.org/r/20200407063621.GA18914@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1586192163-20099-1-git-send-email-laoar.shao@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Oleg Nesterov
b5f2006144 ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()
Commit cc731525f2 ("signal: Remove kernel interal si_code magic")
changed the value of SI_FROMUSER(SI_MESGQ), this means that mq_notify() no
longer works if the sender doesn't have rights to send a signal.

Change __do_notify() to use do_send_sig_info() instead of kill_pid_info()
to avoid check_kill_permission().

This needs the additional notify.sigev_signo != 0 check, shouldn't we
change do_mq_notify() to deny sigev_signo == 0 ?

Test-case:

	#include <signal.h>
	#include <mqueue.h>
	#include <unistd.h>
	#include <sys/wait.h>
	#include <assert.h>

	static int notified;

	static void sigh(int sig)
	{
		notified = 1;
	}

	int main(void)
	{
		signal(SIGIO, sigh);

		int fd = mq_open("/mq", O_RDWR|O_CREAT, 0666, NULL);
		assert(fd >= 0);

		struct sigevent se = {
			.sigev_notify	= SIGEV_SIGNAL,
			.sigev_signo	= SIGIO,
		};
		assert(mq_notify(fd, &se) == 0);

		if (!fork()) {
			assert(setuid(1) == 0);
			mq_send(fd, "",1,0);
			return 0;
		}

		wait(NULL);
		mq_unlink("/mq");
		assert(notified);
		return 0;
	}

[manfred@colorfullife.com: 1) Add self_exec_id evaluation so that the implementation matches do_notify_parent 2) use PIDTYPE_TGID everywhere]
Fixes: cc731525f2 ("signal: Remove kernel interal si_code magic")
Reported-by: Yoji <yoji.fujihar.min@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Cc: <1vier1@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/e2a782e4-eab9-4f5c-c749-c07a8f7a4e66@colorfullife.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00
Suganath Prabu
4778069ccf scsi: mpt3sas: Update maintainers
Updated maintainers list for MPT DRIVERS

Link: https://lore.kernel.org/r/1588056428-29369-1-git-send-email-suganath-prabu.subramani@broadcom.com
Signed-off-by: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:27:11 -04:00
Suganath Prabu
2b01b293f3 scsi: mpt3sas: Capture IOC data for debugging purposes
Information needed to debug driver problems and firmware faults is stored
in the IOC’s MPT3SAS_ADAPTER data structure. Parameters such as IOCFacts,
IOC flags (related to sge, MSI-X, error recovery etc.), performance mode
type, TMs, internal commands reply status, etc. are present.

For debugging purposes, it is therefore helpful to be able to capture this
information so that the fault can be analyzed. Export the MPT3SAS_ADAPTER
data structure in debugfs. The data is available in:

	 /sys/kernel/debug/mpt3sas/scsi_hostX/ioc_dump

Link: https://lore.kernel.org/r/1588056322-29227-1-git-send-email-suganath-prabu.subramani@broadcom.com
Signed-off-by: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:24:27 -04:00
Jason Yan
55d4ce458c scsi: mpt3sas: Use true, false for ioc->use_32bit_dma
Fix the following coccicheck warning:

drivers/scsi/mpt3sas/mpt3sas_base.c:7202:1-19: WARNING: Assignment of
0/1 to bool variable

Link: https://lore.kernel.org/r/20200430121738.15151-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:04:39 -04:00
Jason Yan
013f69a931 scsi: vmw_pvscsi: Use true, false for adapter->use_msg
Fix the following coccicheck warning:

drivers/scsi/vmw_pvscsi.c:911:2-18: WARNING: Assignment of 0/1 to bool
variable

Link: https://lore.kernel.org/r/20200430121729.15064-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:03:54 -04:00
Jason Yan
b91857a5ca scsi: fnic: Use true, false for fnic->internal_reset_inprogress
Fix the following coccicheck warning:

drivers/scsi/fnic/fnic_scsi.c:2627:5-36: WARNING: Comparison of 0/1 to
bool variable

Link: https://lore.kernel.org/r/20200430121718.14970-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:03:07 -04:00
Jason Yan
9187745cee scsi: qedi: Remove comparison of 0/1 to bool variable
Fix the following coccicheck warning:

drivers/scsi/qedi/qedi_main.c:1309:5-25: WARNING: Comparison of 0/1 to
bool variable
drivers/scsi/qedi/qedi_main.c:1315:5-25: WARNING: Comparison of 0/1 to
bool variable

Link: https://lore.kernel.org/r/20200430121706.14879-1-yanaijie@huawei.com
Acked-by: Manish Rangankar <mrangankar@marvell.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:02:19 -04:00
Zou Wei
297083f6e5 scsi: aacraid: Make some symbols static
Fix the following sparse warnings:

drivers/scsi/aacraid/linit.c:867:6: warning:
symbol 'aac_tmf_callback' was not declared. Should it be static?
drivers/scsi/aacraid/linit.c:1081:5: warning:
symbol 'aac_eh_host_reset' was not declared. Should it be static?
drivers/scsi/aacraid/commsup.c:2354:5: warning:
symbol 'aac_send_safw_hostttime' was not declared. Should it be static?
drivers/scsi/aacraid/commsup.c:2383:5: warning:
symbol 'aac_send_hosttime' was not declared. Should it be static?

Link: https://lore.kernel.org/r/1588240932-69020-1-git-send-email-zou_wei@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:01:02 -04:00
Jason Yan
88bfdf565c scsi: qla2xxx: Make qlafx00_process_aen() return void
No other functions use the return value of qlafx00_process_aen() and the
return value is always 0 now. Make it return void. This fixes the following
coccicheck warning:

drivers/scsi/qla2xxx/qla_mr.c:1716:5-9: Unneeded variable: "rval".
Return "0" on line 1768

Link: https://lore.kernel.org/r/20200506061757.19536-1-yanaijie@huawei.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 21:58:58 -04:00
Jason Yan
dbe6f49259 scsi: qla2xxx: Use true, false for ha->fw_dumped
Fix the following coccicheck warning:

drivers/scsi/qla2xxx/qla_tmpl.c:1120:2-20: WARNING: Assignment of 0/1 to
bool variable

Link: https://lore.kernel.org/r/20200430121800.15323-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 21:57:47 -04:00
Jason Yan
bda552a774 scsi: qla2xxx: Use true, false for need_mpi_reset
Fix the following coccicheck warning:

drivers/scsi/qla2xxx/qla_tmpl.c:1031:6-20: WARNING: Assignment of 0/1 to
bool variable
drivers/scsi/qla2xxx/qla_tmpl.c:1062:3-17: WARNING: Assignment of 0/1 to
bool variable

Link: https://lore.kernel.org/r/20200430121751.15232-1-yanaijie@huawei.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 21:56:38 -04:00
Jason Yan
1b007f96f9 scsi: qla2xxx: Make qla_set_ini_mode() return void
The return value is not used by the caller and the local variable 'rc' is
not needed. Make qla_set_ini_mode() return void and remove 'rc'.  This also
fixes the following coccicheck warning:

drivers/scsi/qla2xxx/qla_attr.c:1906:5-7: Unneeded variable: "rc".
Return "0" on line 2180

Link: https://lore.kernel.org/r/20200429140952.8240-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 21:54:42 -04:00
Gustavo A. R. Silva
60da7d0bc7 sparc64: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07 18:49:04 -07:00