Linux kernel
============
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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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s390 has a swap_ex_entry_fixup function, however it is not being used
since common code expects a swap_ex_entry_fixup define. If it is not
defined the default implementation will be used. So fix this by adding
a proper define.
However also the implementation of the function must be fixed, since a
NULL value for handler has a special meaning and must not be adjusted.
Luckily all of this doesn't fix a real bug currently: the main extable
is correctly sorted during build time, and for runtime sorting there
is currently no case where the handler field is not NULL.
Fixes: 05a68e892e89 ("s390/kernel: expand exception table logic to allow new handling options")
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
arch_ftrace_get_regs is supposed to return a struct pt_regs pointer
only if the pt_regs structure contains all register contents, which
means it must have been populated when created via ftrace_regs_caller.
If it was populated via ftrace_caller the contents are not complete
(the psw mask part is missing), and therefore a NULL pointer needs be
returned.
The current code incorrectly always returns a struct pt_regs pointer.
Fix this by adding another pt_regs flag which indicates if the
contents are complete, and fix arch_ftrace_get_regs accordingly.
Fixes: 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations")
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reported-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
ftrace_caller was used for both ftrace_caller and ftrace_regs_caller,
which means that the target address of the hotpatch trampoline was
never updated.
With commit 894979689d3a ("s390/ftrace: provide separate
ftrace_caller/ftrace_regs_caller implementations") a separate
ftrace_regs_caller entry point was implemeted, however it was
forgotten to implement the necessary changes for ftrace_modify_call
and ftrace_make_call, where the branch target has to be modified
accordingly.
Therefore add the missing code now.
Fixes: 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations")
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
We need to preserve the values at OLDMEM_BASE and OLDMEM_SIZE which are
used by zgetdump in case when kdump crashes. In that case zgetdump will
attempt to read OLDMEM_BASE and OLDMEM_SIZE in order to find out where
the memory range [0 - OLDMEM_SIZE] belonging to the production kernel is.
Fixes: f1a546947431 ("s390/setup: don't reserve memory that occupied decompressor's head")
Cc: stable@vger.kernel.org # 5.15+
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
If no driver is attached to a device or the driver does not provide the
path_event function, an FCES path-event on this device could end up in a
kernel-panic. Verify the driver availability before the path_event
function call.
Fixes: 32ef938815c1 ("s390/cio: Add support for FCES status notification")
Cc: stable@vger.kernel.org
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Suggested-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Move test_modules_return_* prototypes into a header file in order to
placate -Wmissing-prototypes.
Fixes: 90c5318795ee ("s390/module: test loading modules with a lot of relocations")
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Now that Alexander Gordeev has volunteered to be a co-maintainer for
s390, I can act as a reviewer instead of being a maintainer for s390.
With Alexander, Heiko, and Vasily we are in really good shape.
I will continue to act as the maintainer for KVM on s390 together with
Janosch.
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Change Alexander Gordeev's status so he is maintainer
instead of reviewer for s390.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull ext4 fixes from Ted Ts'o:
"Various bug fixes for ext4 fast commit and inline data handling.
Also fix regression introduced as part of moving to the new mount API"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
fs/ext4: fix comments mentioning i_mutex
ext4: fix incorrect type issue during replay_del_range
jbd2: fix kernel-doc descriptions for jbd2_journal_shrink_{scan,count}()
ext4: fix potential NULL pointer dereference in ext4_fill_super()
jbd2: refactor wait logic for transaction updates into a common function
jbd2: cleanup unused functions declarations from jbd2.h
ext4: fix error handling in ext4_fc_record_modified_inode()
ext4: remove redundant max inline_size check in ext4_da_write_inline_data_begin()
ext4: fix error handling in ext4_restore_inline_data()
ext4: fast commit may miss file actions
ext4: fast commit may not fallback for ineligible commit
ext4: modify the logic of ext4_mb_new_blocks_simple
ext4: prevent used blocks from being allocated during fast commit replay
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix display of grouped aliased events in 'perf stat'.
- Add missing branch_sample_type to perf_event_attr__fprintf().
- Apply correct label to user/kernel symbols in branch mode.
- Fix 'perf ftrace' system_wide tracing, it has to be set before
creating the maps.
- Return error if procfs isn't mounted for PID namespaces when
synthesizing records for pre-existing processes.
- Set error stream of objdump process for 'perf annotate' TUI, to avoid
garbling the screen.
- Add missing arm64 support to perf_mmap__read_self(), the kernel part
got into 5.17.
- Check for NULL pointer before dereference writing debug info about a
sample.
- Update UAPI copies for asound, perf_event, prctl and kvm headers.
- Fix a typo in bpf_counter_cgroup.c.
* tag 'perf-tools-fixes-for-v5.17-2022-02-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf ftrace: system_wide collection is not effective by default
libperf: Add arm64 support to perf_mmap__read_self()
tools include UAPI: Sync sound/asound.h copy with the kernel sources
perf stat: Fix display of grouped aliased events
perf tools: Apply correct label to user/kernel symbols in branch mode
perf bpf: Fix a typo in bpf_counter_cgroup.c
perf synthetic-events: Return error if procfs isn't mounted for PID namespaces
perf session: Check for NULL pointer before dereference
perf annotate: Set error stream of objdump process for TUI
perf tools: Add missing branch_sample_type to perf_event_attr__fprintf()
tools headers UAPI: Sync linux/kvm.h with the kernel sources
tools headers UAPI: Sync linux/prctl.h with the kernel sources
perf beauty: Make the prctl arg regexp more strict to cope with PR_SET_VMA
tools headers cpufeatures: Sync with the kernel sources
tools headers UAPI: Sync linux/perf_event.h with the kernel sources
tools include UAPI: Sync sound/asound.h copy with the kernel sources
inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix
comments still mentioning i_mutex.
Signed-off-by: hongnanli <hongnan.li@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220121070611.21618-1-hongnan.li@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull perf fixes from Borislav Petkov:
- Intel/PT: filters could crash the kernel
- Intel: default disable the PMU for SMM, some new-ish EFI firmware has
started using CPL3 and the PMU CPL filters don't discriminate against
SMM, meaning that CPL3 (userspace only) events now also count EFI/SMM
cycles.
- Fixup for perf_event_attr::sig_data
* tag 'perf_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/pt: Fix crash with stop filters in single-range mode
perf: uapi: Document perf_event_attr::sig_data truncation on 32 bit architectures
selftests/perf_events: Test modification of perf_event_attr::sig_data
perf: Copy perf_event_attr::sig_data on modification
x86/perf: Default set FREEZE_ON_SMI for all