Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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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Pull Kbuild fixes from Masahiro Yamada:
- Fix UNUSED_KSYMS_WHITELIST for Clang LTO
- Make -s builds really silent irrespective of V= option
- Fix build error when SUBLEVEL or PATCHLEVEL is empty
* tag 'kbuild-fixes-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: Fix <linux/version.h> for empty SUBLEVEL or PATCHLEVEL again
kbuild: make -s option take precedence over V=1
ia64: remove redundant READELF from arch/ia64/Makefile
kbuild: do not include include/config/auto.conf from adjust_autoksyms.sh
kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO
kbuild: lto: add _mcount to list of used symbols
Pull arch/csky updates from Guo Ren:
"Features:
- add new memory layout 2.5G(user):1.5G(kernel)
- add kmemleak support
- reconstruct VDSO framework: add VDSO with GENERIC_GETTIMEOFDAY,
GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO
- add faulthandler_disabled() check
- support (fix) swapon
- add (fix) _PAGE_ACCESSED for default pgprot
- abort uaccess retries upon fatal signal (from arm)
Fixes and optimizations:
- fix perf probe failure
- fix show_regs doesn't contain regs->usp
- remove custom asm/atomic.h implementation
- fix barrier design
- fix futex SMP implementation
- fix asm/cmpxchg.h with correct ordering barrier
- cleanup asm/spinlock.h
- fix PTE global for 2.5:1.5 virtual memory
- remove prologue of page fault handler in entry.S
- fix TLB maintenance synchronization problem
- add show_tlb for CPU_CK860 debug
- fix FAULT_FLAG_XXX param for handle_mm_fault
- fix update_mmu_cache called with user io mapping
- fix do_page_fault parent irq status
- fix a size determination in gpr_get()
- pgtable.h: Coding convention
- kprobe: Fix code in simulate without 'long'
- fix pfn_valid error with wrong max_mapnr
- use free_initmem_default() in free_initmem()
- fix compile error"
* tag 'csky-for-linus-5.12-rc1' of git://github.com/c-sky/csky-linux: (30 commits)
csky: Fixup compile error
csky: use free_initmem_default() in free_initmem()
csky: Fixup pfn_valid error with wrong max_mapnr
csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO
csky: kprobe: Fixup code in simulate without 'long'
csky: Fixup swapon
csky: pgtable.h: Coding convention
csky: Fixup _PAGE_ACCESSED for default pgprot
csky: remove unused including <linux/version.h>
csky: Fix a size determination in gpr_get()
csky: Reconstruct VDSO framework
csky: mm: abort uaccess retries upon fatal signal
csky: Sync riscv mm/fault.c for easy maintenance
csky: Fixup do_page_fault parent irq status
csky: Add faulthandler_disabled() check
csky: Fixup update_mmu_cache called with user io mapping
csky: Fixup FAULT_FLAG_XXX param for handle_mm_fault
csky: Add show_tlb for CPU_CK860 debug
csky: Fix TLB maintenance synchronization problem
csky: Add kmemleak support
...
Commit 78d3bb4483ba ("kbuild: Fix <linux/version.h> for empty SUBLEVEL
or PATCHLEVEL") fixed the build error for empty SUBLEVEL or PATCHLEVEL
by prepending a zero.
Commit 9b82f13e7ef3 ("kbuild: clamp SUBLEVEL to 255") re-introduced
this issue.
This time, we cannot take the same approach because we have C code:
#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL)
#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
Replace empty SUBLEVEL/PATCHLEVEL with a zero.
Fixes: 9b82f13e7ef3 ("kbuild: clamp SUBLEVEL to 255")
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-and-tested-by: Sasha Levin <sashal@kernel.org>
Pull more RISC-V updates from Palmer Dabbelt:
"A pair of patches that slipped through the cracks:
- enable CPU hotplug in the defconfigs
- some cleanups to setup_bootmem
There's also a single fix for some randconfig build failures:
- make NUMA depend on SMP"
* tag 'riscv-for-linus-5.12-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Cleanup setup_bootmem()
RISC-V: Enable CPU Hotplug in defconfigs
RISC-V: Make NUMA depend on SMP
: error: C++ style comments are not allowed in ISO C90
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
^
error: (this will be reported only once per input file)
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
'make -s' should be really silent. However, 'make -s V=1' prints noisy
log messages from some shell scripts.
Of course, such a combination is odd, but the build system needs to do
the right thing even if a user gives strange input.
If -s is given, KBUILD_VERBOSE should be forced to 0.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull more SCSI updates from James Bottomley:
"This is a few driver updates (iscsi, mpt3sas) that were still in the
staging queue when the merge window opened (all committed on or before
8 Feb) and some small bug fixes which came in during the merge window
(all committed on 22 Feb)"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (30 commits)
scsi: hpsa: Correct dev cmds outstanding for retried cmds
scsi: sd: Fix Opal support
scsi: target: tcmu: Fix memory leak caused by wrong uio usage
scsi: target: tcmu: Move some functions without code change
scsi: sd: sd_zbc: Don't pass GFP_NOIO to kvcalloc
scsi: aic7xxx: Remove unused function pointer typedef ahc_bus_suspend/resume_t
scsi: bnx2fc: Fix Kconfig warning & CNIC build errors
scsi: ufs: Fix a duplicate dev quirk number
scsi: aic79xx: Fix spelling of version
scsi: target: core: Prevent underflow for service actions
scsi: target: core: Add cmd length set before cmd complete
scsi: iscsi: Drop session lock in iscsi_session_chkready()
scsi: qla4xxx: Use iscsi_is_session_online()
scsi: libiscsi: Reset max/exp cmdsn during recovery
scsi: iscsi_tcp: Fix shost can_queue initialization
scsi: libiscsi: Add helper to calculate max SCSI cmds per session
scsi: libiscsi: Fix iSCSI host workq destruction
scsi: libiscsi: Fix iscsi_task use after free()
scsi: libiscsi: Drop taskqueuelock
scsi: libiscsi: Fix iscsi_prep_scsi_cmd_pdu() error handling
...
After the following patches,
commit de043da0b9e7 ("RISC-V: Fix usage of memblock_enforce_memory_limit")
commit 1bd14a66ee52 ("RISC-V: Remove any memblock representing unusable memory area")
commit b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()")
some logic is useless, kill the mem_start/start/end and unneeded code.
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The existing code is essentially
free_initmem_default()->free_reserved_area() without poisoning.
Note that existing code missed to update the managed page count of the
zone.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Tested-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Guo Ren <guoren@kernel.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
READELF is defined by the top Makefile.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull more xfs updates from Darrick Wong:
"The most notable fix here prevents premature reuse of freed metadata
blocks, and adding the ability to detect accidental nested
transactions, which are not allowed here.
- Restore a disused sysctl control knob that was inadvertently
dropped during the merge window to avoid fstests regressions.
- Don't speculatively release freed blocks from the busy list until
we're actually allocating them, which fixes a rare log recovery
regression.
- Don't nest transactions when scanning for free space.
- Add an idiot^Wmaintainer light to detect nested transactions. ;)"
* tag 'xfs-5.12-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: use current->journal_info for detecting transaction recursion
xfs: don't nest transactions when scanning for eofblocks
xfs: don't reuse busy extents on extent trim
xfs: restore speculative_cow_prealloc_lifetime sysctl
Prevent incrementing device->commands_outstanding for ioaccel command
retries that are driver initiated. If the command goes through the retry
path, the device->commands_outstanding counter has already accounted for
the number of commands outstanding to the device. Only commands going
through function hpsa_cmd_resolve_events decrement this counter.
- ioaccel commands go to either HBA disks or to logical volumes comprised
of SSDs.
The extra increment is causing device resets to hang.
- Resets wait for all device outstanding commands to complete before
returning.
Replace unused field abort_pending with retry_pending. This is a
maintenance driver so these changes have the least impact/risk.
Link: https://lore.kernel.org/r/161342801747.29388.13045495968308188518.stgit@brunhilda
Tested-by: Joe Szczypek <jszczype@redhat.com>
Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The CPU hotplug support has been tested on QEMU, Spike, and SiFive
Unleashed so let's enable it by default in RV32 and RV64 defconfigs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>