Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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That logic is unused since
320100a5ffe5 ("x86/entry: Remove the TRACE_IRQS cruft")
Remove it.
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/YAAszZJ2GcIYZmB5@hirez.programming.kicks-ass.net
Arnd found a randconfig that produces the warning:
arch/x86/entry/thunk_64.o: warning: objtool: missing symbol for insn at
offset 0x3e
when building with LLVM_IAS=1 (Clang's integrated assembler). Josh
notes:
With the LLVM assembler not generating section symbols, objtool has no
way to reference this code when it generates ORC unwinder entries,
because this code is outside of any ELF function.
The limitation now being imposed by objtool is that all code must be
contained in an ELF symbol. And .L symbols don't create such symbols.
So basically, you can use an .L symbol *inside* a function or a code
segment, you just can't use the .L symbol to contain the code using a
SYM_*_START/END annotation pair.
Fangrui notes that this optimization is helpful for reducing image size
when compiling with -ffunction-sections and -fdata-sections. I have
observed on the order of tens of thousands of symbols for the kernel
images built with those flags.
A patch has been authored against GNU binutils to match this behavior
of not generating unused section symbols ([1]), so this will
also become a problem for users of GNU binutils once they upgrade to 2.36.
Omit the .L prefix on a label so that the assembler will emit an entry
into the symbol table for the label, with STB_LOCAL binding. This
enables objtool to generate proper unwind info here with LLVM_IAS=1 or
GNU binutils 2.36+.
[ bp: Massage commit message. ]
Reported-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20210112194625.4181814-1-ndesaulniers@google.com
Link: https://github.com/ClangBuiltLinux/linux/issues/1209
Link: https://reviews.llvm.org/D93783
Link: https://sourceware.org/binutils/docs/as/Symbol-Names.html
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d1bcae833b32f1408485ce69f844dcd7ded093a8 [1]
Pull Kbuild fixes from Masahiro Yamada:
- Search for <ncurses.h> in the default header path of HOSTCC
- Tweak the option order to be kind to old BSD awk
- Remove 'kvmconfig' and 'xenconfig' shorthands
- Fix documentation
* tag 'kbuild-fixes-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
Documentation: kbuild: Fix section reference
kconfig: remove 'kvmconfig' and 'xenconfig' shorthands
lib/raid6: Let $(UNROLL) rules work with macOS userland
kconfig: Support building mconf with vendor sysroot ncurses
kconfig: config script: add a little user help
MAINTAINERS: adjust GCC PLUGINS after gcc-plugin.sh removal
Pull SCSI fixes from James Bottomley:
"This is two driver fixes (megaraid_sas and hisi_sas).
The megaraid one is a revert of a previous revert of a cpu hotplug fix
which exposed a bug in the block layer which has been fixed in this
merge window.
The hisi_sas performance enhancement comes from switching to interrupt
managed completion queues, which depended on the addition of
devm_platform_get_irqs_affinity() which is now upstream via the irq
tree in the last merge window"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: hisi_sas: Expose HW queues for v2 hw
Revert "Revert "scsi: megaraid_sas: Added support for shared host tagset for cpuhotplug""
Section 3.11 was incorrectly called 3.9, fix it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull block fixes from Jens Axboe:
- Missing CRC32 selections (Arnd)
- Fix for a merge window regression with bdev inode init (Christoph)
- bcache fixes
- rnbd fixes
- NVMe pull request from Christoph:
- fix a race in the nvme-tcp send code (Sagi Grimberg)
- fix a list corruption in an nvme-rdma error path (Israel Rukshin)
- avoid a possible double fetch in nvme-pci (Lalithambika Krishnakumar)
- add the susystem NQN quirk for a Samsung driver (Gopal Tiwari)
- fix two compiler warnings in nvme-fcloop (James Smart)
- don't call sleeping functions from irq context in nvme-fc (James Smart)
- remove an unused argument (Max Gurtovoy)
- remove unused exports (Minwoo Im)
- Use-after-free fix for partition iteration (Ming)
- Missing blk-mq debugfs flag annotation (John)
- Bdev freeze regression fix (Satya)
- blk-iocost NULL pointer deref fix (Tejun)
* tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block: (26 commits)
bcache: set bcache device into read-only mode for BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET
bcache: introduce BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE for large bucket
bcache: check unsupported feature sets for bcache register
bcache: fix typo from SUUP to SUPP in features.h
bcache: set pdev_set_uuid before scond loop iteration
blk-mq-debugfs: Add decode for BLK_MQ_F_TAG_HCTX_SHARED
block/rnbd-clt: avoid module unload race with close confirmation
block/rnbd: Adding name to the Contributors List
block/rnbd-clt: Fix sg table use after free
block/rnbd-srv: Fix use after free in rnbd_srv_sess_dev_force_close
block/rnbd: Select SG_POOL for RNBD_CLIENT
block: pre-initialize struct block_device in bdev_alloc_inode
fs: Fix freeze_bdev()/thaw_bdev() accounting of bd_fsfreeze_sb
nvme: remove the unused status argument from nvme_trace_bio_complete
nvmet-rdma: Fix list_del corruption on queue establishment failure
nvme: unexport functions with no external caller
nvme: avoid possible double fetch in handling CQE
nvme-tcp: Fix possible race of io_work and direct send
nvme-pci: mark Samsung PM1725a as IGNORE_DEV_SUBNQN
nvme-fcloop: Fix sscanf type and list_first_entry_or_null warnings
...
Merge two commits that had dependencies on other 5.11 trees (the block
and the irq trees respectively).
- We reverted a megaraid_sas change in 5.10 due to missing block
layer plumbing. Now that this is in place, reinstate the change.
- The hisi_sas driver had a dependency on a driver core irq change
that went in through Thomas' tree.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux 5.10 is out. Remove the 'kvmconfig' and 'xenconfig' shorthands
as previously announced.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull io_uring fixes from Jens Axboe:
"A bit larger than I had hoped at this point, but it's all changes that
will be directed towards stable anyway. In detail:
- Fix a merge window regression on error return (Matthew)
- Remove useless variable declaration/assignment (Ye Bin)
- IOPOLL fixes (Pavel)
- Exit and cancelation fixes (Pavel)
- fasync lockdep complaint fix (Pavel)
- Ensure SQPOLL is synchronized with creator life time (Pavel)"
* tag 'io_uring-5.11-2021-01-10' of git://git.kernel.dk/linux-block:
io_uring: stop SQPOLL submit on creator's death
io_uring: add warn_once for io_uring_flush()
io_uring: inline io_uring_attempt_task_drop()
io_uring: io_rw_reissue lockdep annotations
io_uring: synchronise ev_posted() with waitqueues
io_uring: dont kill fasync under completion_lock
io_uring: trigger eventfd for IOPOLL
io_uring: Fix return value from alloc_fixed_file_ref_node
io_uring: Delete useless variable ‘id’ in io_prep_async_work
io_uring: cancel more aggressively in exit_work
io_uring: drop file refs after task cancel
io_uring: patch up IOPOLL overflow_flush sync
io_uring: synchronise IOPOLL on task_submit fail
If BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET is set in incompat feature
set, it means the cache device is created with obsoleted layout with
obso_bucket_site_hi. Now bcache does not support this feature bit, a new
BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE incompat feature bit is added
for a better layout to support large bucket size.
For the legacy compatibility purpose, if a cache device created with
obsoleted BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit, all bcache
devices attached to this cache set should be set to read-only. Then the
dirty data can be written back to backing device before re-create the
cache device with BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE feature bit
by the latest bcache-tools.
This patch checks BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit
when running a cache set and attach a bcache device to the cache set. If
this bit is set,
- When run a cache set, print an error kernel message to indicate all
following attached bcache device will be read-only.
- When attach a bcache device, print an error kernel message to indicate
the attached bcache device will be read-only, and ask users to update
to latest bcache-tools.
Such change is only for cache device whose bucket size >= 32MB, this is
for the zoned SSD and almost nobody uses such large bucket size at this
moment. If you don't explicit set a large bucket size for a zoned SSD,
such change is totally transparent to your bcache device.
Fixes: ffa470327572 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As a performance enhancement, make the completion queue interrupts managed.
In addition, in commit bf0beec0607d ("blk-mq: drain I/O when all CPUs in a
hctx are offline"), CPU hotplug for MQ devices using managed interrupts is
made safe. So expose HW queues to blk-mq to take advantage of this.
Flag Scsi_host.host_tagset is also set to ensure that the HBA is not sent
more commands than it can handle. However the driver still does not use
request tag for IPTT as there are many HW bugs means that special rules
apply for IPTT allocation.
Link: https://lore.kernel.org/r/1606905417-183214-6-git-send-email-john.garry@huawei.com
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>