Before this patch, all io errors received by the quota daemon or the
logd daemon would cause a complaint message to be issued, such as:
gfs2: fsid=dm-13.0: Error 10 writing to journal, jid=0
This patch changes it so that the error message is only issued the
first time the error is encountered.
Also, before this patch function gfs2_end_log_write did not set the
sd_log_error value, so log errors would not cause the file system to
be withdrawn. This patch sets the error code so the file system is
properly withdrawn if an io error is encountered writing to the journal.
WARNING: This change in function breaks check xfstests generic/441
and causes it to fail: io errors writing to the log should cause a
file system to be withdrawn, and no further operations are tolerated.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, gfs2 kept track of journal io errors in two
places sd_log_error and the SDF_AIL1_IO_ERROR flag in sd_flags.
This patch consolidates the two into sd_log_error so that it
reflects the first error encountered writing to the journal.
In future patches, we will take advantage of this by checking
this value rather than having to check both when reacting to
io errors.
In addition, this fixes a tight loop in unmount: If buffers
get on the ail1 list and an io error occurs elsewhere, the
ail1 list would never be cleared because they were always busy.
So unmount would hang, waiting for the ail1 list to empty.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, the rgrp code had a serious problem related to
how it managed buffer_heads for resource groups. The problem caused
file system corruption, especially in cases of journal replay.
When an rgrp glock was demoted to transfer ownership to a
different cluster node, do_xmote() first calls rgrp_go_sync and then
rgrp_go_inval, as expected. When it calls rgrp_go_sync, that called
gfs2_rgrp_brelse() that dropped the buffer_head reference count.
In most cases, the reference count went to zero, which is right.
However, there were other places where the buffers are handled
differently.
After rgrp_go_sync, do_xmote called rgrp_go_inval which called
gfs2_rgrp_brelse a second time, then rgrp_go_inval's call to
truncate_inode_pages_range would get rid of the pages in memory,
but only if the reference count drops to 0.
Unfortunately, gfs2_rgrp_brelse was setting bi->bi_bh = NULL.
So when rgrp_go_sync called gfs2_rgrp_brelse, it lost the pointer
to the buffer_heads in cases where the reference count was still 1.
Therefore, when rgrp_go_inval called gfs2_rgrp_brelse a second time,
it failed the check for "if (bi->bi_bh)" and thus failed to call
brelse a second time. Because of that, the reference count on those
buffers sometimes failed to drop from 1 to 0. And that caused
function truncate_inode_pages_range to keep the pages in page cache
rather than freeing them.
The next time the rgrp glock was acquired, the metadata read of
the rgrp buffers re-used the pages in memory, which were now
wrong because they were likely modified by the other node who
acquired the glock in EX (which is why we demoted the glock).
This re-use of the page cache caused corruption because changes
made by the other nodes were never seen, so the bitmaps were
inaccurate.
For some reason, the problem became most apparent when journal
replay forced the replay of rgrps in memory, which caused newer
rgrp data to be overwritten by the older in-core pages.
A big part of the problem was that the rgrp buffer were released
in multiple places: The go_unlock function would release them when
the glock was released rather than when the glock is demoted,
which is clearly wrong because our intent was to cache them until
the glock is demoted from SH or EX.
This patch attempts to clean up the mess and make one consistent
and centralized mechanism for managing the rgrp buffer_heads by
implementing several changes:
1. It eliminates the call to gfs2_rgrp_brelse() from rgrp_go_sync.
We don't want to release the buffers or zero the pointers when
syncing for the reasons stated above. It only makes sense to
release them when the glock is actually invalidated (go_inval).
And when we do, then we set the bh pointers to NULL.
2. The go_unlock function (which was only used for rgrps) is
eliminated, as we've talked about doing many times before.
The go_unlock function was called too early in the glock dq
process, and should not happen until the glock is invalidated.
3. It also eliminates the call to rgrp_brelse in gfs2_clear_rgrpd.
That will now happen automatically when the rgrp glocks are
demoted, and shouldn't happen any sooner or later than that.
Instead, function gfs2_clear_rgrpd has been modified to demote
the rgrp glocks, and therefore, free those pages, before the
remaining glocks are culled by gfs2_gl_hash_clear. This
prevents the gl_object from hanging around when the glocks are
culled.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch fixes a bug in which function gfs2_log_flush can get into
an infinite loop when a gfs2 file system is withdrawn. The problem
is the infinite loop "for (;;)" in gfs2_log_flush which would never
finish because the io error and subsequent withdraw prevented the
items from being taken off the ail list.
This patch tries to clean up the mess by allowing withdraw situations
to move not-in-flight buffer_heads to the ail2 list, where they will
be dealt with later.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
File system withdraws can be delayed when inconsistencies are
discovered when we cannot withdraw immediately, for example, when
critical spin_locks are held. But delaying the withdraw can cause
gfs2 to ignore the error and keep running for a short period of time.
For example, an rgrp glock may be dequeued and demoted while there
are still buffers that haven't been properly revoked, due to io
errors writing to the journal.
This patch introduces a new concept of a pending withdraw, which
means an inconsistency has been discovered and we need to withdraw
at the earliest possible opportunity. In these cases, we aren't
quite withdrawn yet, but we still need to not dequeue glocks and
other critical things. If we dequeue the glocks and the withdraw
results in our journal being replayed, the replay could overwrite
data that's been modified by a different node that acquired the
glock in the meantime.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
The gfs2_assert functions only print messages when the filesystem hasn't been
withdrawn yet, and they indicate whether or not they've printed something in
their return value. However, none of the callers use that information, so
simply return whether or not the assert has failed.
(The gfs2_assert functions are still backwards; they return false when an
assertion is true.)
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Change the various gfs2_consist functions to return void.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
These arguments are always passed as 0, and they are never evaluated.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
In gfs2_rgrp_verify and compute_bitstructs, make sure to report errors before
withdrawing the filesystem: otherwise, when we withdraw first and withdraw is
configured to panic, we'll never get to the error reporting.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Split gfs2_lm_withdraw into a function that prints an error message and a
function that withdraws the filesystem.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
In gfs2_file_write_iter, for direct writes, the error checking in the buffered
write fallback case is incomplete. This can cause inode write errors to go
undetected. Fix and clean up gfs2_file_write_iter along the way.
Based on a proposed fix by Christoph Hellwig <hch@lst.de>.
Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Set current->backing_dev_info just around the buffered write calls to
prepare for the next fix.
Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When the first log header in a journal happens to have a sequence
number of 0, a bug in gfs2_find_jhead() causes it to prematurely exit,
and return an uninitialized jhead with seq 0. This can cause failures
in the caller. For instance, a mount fails in one test case.
The correct behavior is for it to continue searching through the journal
to find the correct journal head with the highest sequence number.
Fixes: f4686c26ec ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Fix some corner cases on filesystems with a block size < page size.
- Fix a corner case that could expose incorrect access times over nfs.
- Revert an otherwise sensible revoke accounting cleanup that causes
assertion failures. The revoke accounting is whacky and needs to be
fixed properly before we can add back this cleanup.
- Various other minor cleanups.
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Merge tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Fix some corner cases on filesystems with a block size < page size.
- Fix a corner case that could expose incorrect access times over nfs.
- Revert an otherwise sensible revoke accounting cleanup that causes
assertion failures. The revoke accounting is whacky and needs to be
fixed properly before we can add back this cleanup.
- Various other minor cleanups.
In addition, please expect to see another pull request from Bob Peterson
about his gfs2 recovery patch queue shortly.
* tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
Revert "gfs2: eliminate tr_num_revoke_rm"
gfs2: remove unused LBIT macros
fs/gfs2: remove unused IS_DINODE and IS_LEAF macros
gfs2: Remove GFS2_MIN_LVB_SIZE define
gfs2: Fix incorrect variable name
gfs2: Avoid access time thrashing in gfs2_inode_lookup
gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepage
gfs2: eliminate ssize parameter from gfs2_struct2blk
gfs2: Another gfs2_find_jhead fix
- Fix an off-by-one error when checking if offset is within inode size
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Merge tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fix from Darrick Wong:
"A single patch fixing an off-by-one error when we're checking to see
how far we're gotten into an EOF page"
* tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
fs: Fix page_mkwrite off-by-one errors
Pull updates from Andrew Morton:
"Most of -mm and quite a number of other subsystems: hotfixes, scripts,
ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov.
MM is fairly quiet this time. Holidays, I assume"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
kcov: ignore fault-inject and stacktrace
include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc()
execve: warn if process starts with executable stack
reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()
init/main.c: fix misleading "This architecture does not have kernel memory protection" message
init/main.c: fix quoted value handling in unknown_bootoption
init/main.c: remove unnecessary repair_env_string in do_initcall_level
init/main.c: log arguments and environment passed to init
fs/binfmt_elf.c: coredump: allow process with empty address space to coredump
fs/binfmt_elf.c: coredump: delete duplicated overflow check
fs/binfmt_elf.c: coredump: allocate core ELF header on stack
fs/binfmt_elf.c: make BAD_ADDR() unlikely
fs/binfmt_elf.c: better codegen around current->mm
fs/binfmt_elf.c: don't copy ELF header around
fs/binfmt_elf.c: fix ->start_code calculation
fs/binfmt_elf.c: smaller code generation around auxv vector fill
lib/find_bit.c: uninline helper _find_next_bit()
lib/find_bit.c: join _find_next_bit{_le}
uapi: rename ext2_swab() to swab() and share globally in swab.h
lib/scatterlist.c: adjust indentation in __sg_alloc_table
...
Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings to
indicate to the linker that it can perform string deduplication (i.e.,
duplicate strings are reduced to a single copy in the string table).
This means any repeated namespace string would be merged to just one
entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error path,
improve moduleparam docs, silence rcu warnings, improve error logging)
Signed-off-by: Jessica Yu <jeyu@kernel.org>
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Merge tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings
to indicate to the linker that it can perform string deduplication
(i.e., duplicate strings are reduced to a single copy in the string
table). This means any repeated namespace string would be merged to
just one entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error
path, improve moduleparam docs, silence rcu warnings, improve error
logging)"
* tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module.h: Annotate mod_kallsyms with __rcu
module: avoid setting info->name early in case we can fall back to info->mod->name
modsign: print module name along with error message
kernel/module: Fix memleak in module_add_modinfo_attrs()
export.h: reduce __ksymtab_strings string duplication by using "MS" section flags
moduleparam: fix kerneldoc
modules: lockdep: Suppress suspicious RCU usage warning
- Support mremap() for the VDSO, primarily to allow CRIU to restore the
VDSO to its checkpointed location.
- Restore the MIPS32 cBPF JIT, after having reverted the enablement of
the eBPF JIT for MIPS32 systems in the 5.5 cycle.
- Improve cop0 counter synchronization behaviour whilst onlining CPUs by
running with interrupts disabled.
- Better match FPU behaviour when emulating multiply-accumulate
instructions on pre-r6 systems that implement IEEE754-2008 style MACs.
- Loongson64 kernels now build using the MIPS64r2 ISA, allowing them to
take advantage of instructions introduced by r2.
- Support for the Ingenic X1000 SoC & the really nice little CU Neo
development board that's using it.
- Support for WMAC on GARDENA Smart Gateway devices.
- Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
preparation for introducing IP35 (Origin 3*) support.
- Various Kconfig & Makefile cleanups.
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Merge tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS changes from Paul Burton:
"Nothing too big or scary in here:
- Support mremap() for the VDSO, primarily to allow CRIU to restore
the VDSO to its checkpointed location.
- Restore the MIPS32 cBPF JIT, after having reverted the enablement
of the eBPF JIT for MIPS32 systems in the 5.5 cycle.
- Improve cop0 counter synchronization behaviour whilst onlining CPUs
by running with interrupts disabled.
- Better match FPU behaviour when emulating multiply-accumulate
instructions on pre-r6 systems that implement IEEE754-2008 style
MACs.
- Loongson64 kernels now build using the MIPS64r2 ISA, allowing them
to take advantage of instructions introduced by r2.
- Support for the Ingenic X1000 SoC & the really nice little CU Neo
development board that's using it.
- Support for WMAC on GARDENA Smart Gateway devices.
- Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
preparation for introducing IP35 (Origin 3*) support.
- Various Kconfig & Makefile cleanups"
* tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (60 commits)
MIPS: PCI: Add detection of IOC3 on IO7, IO8, IO9 and Fuel
MIPS: Loongson64: Disable exec hazard
MIPS: Loongson64: Bump ISA level to MIPSR2
MIPS: Make DIEI support as a config option
MIPS: OCTEON: octeon-irq: fix spelling mistake "to" -> "too"
MIPS: asm: local: add barriers for Loongson
MIPS: Loongson64: Select mac2008 only feature
MIPS: Add MAC2008 Support
Revert "MIPS: Add custom serial.h with BASE_BAUD override for generic kernel"
MIPS: sort MIPS and MIPS_GENERIC Kconfig selects alphabetically (again)
MIPS: make CPU_HAS_LOAD_STORE_LR opt-out
MIPS: generic: don't unconditionally select PINCTRL
MIPS: don't explicitly select LIBFDT in Kconfig
MIPS: sync-r4k: do slave counter synchronization with disabled HW interrupts
MIPS: SGI-IP30: Check for valid pointer before using it
MIPS: syscalls: fix indentation of the 'SYSNR' message
MIPS: boot: fix typo in 'vmlinux.lzma.its' target
MIPS: fix indentation of the 'RELOCS' message
dt-bindings: Document loongson vendor-prefix
MIPS: CU1000-Neo: Refresh defconfig to support HWMON and WiFi.
...
This tag contains a handful of patches that I'd like to target for this merge
window:
* Support for kasan.
* 32-bit physical addresses on rv32i-based systems.
* Support for CONFIG_DEBUG_VIRTUAL
* DT entry for the FU540 GPIO controller, which has recently had a device
driver merged.
These boot a buildroot-based system on QEMU's virt board for me.
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Merge tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains a handful of patches for this merge window:
- Support for kasan
- 32-bit physical addresses on rv32i-based systems
- Support for CONFIG_DEBUG_VIRTUAL
- DT entry for the FU540 GPIO controller, which has recently had a
device driver merged
These boot a buildroot-based system on QEMU's virt board for me"
* tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: dts: Add DT support for SiFive FU540 GPIO driver
riscv: mm: add support for CONFIG_DEBUG_VIRTUAL
riscv: keep 32-bit kernel to 32-bit phys_addr_t
kasan: Add riscv to KASAN documentation.
riscv: Add KASAN support
kasan: No KASAN's memmove check if archs don't have it.
Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- three fixes and a cleanup for the resctrl code
- a HyperV fix
- a fix to /proc/kcore contents in live debugging sessions
- a fix for the x86 decoder opcode map"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/decoder: Add TEST opcode to Group3-2
x86/resctrl: Clean up unused function parameter in mkdir path
x86/resctrl: Fix a deadlock due to inaccurate reference
x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
x86/resctrl: Fix use-after-free when deleting resource groups
x86/hyper-v: Add "polling" bit to hv_synic_sint
x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
Don't instrument 3 more files that contain debugging facilities and
produce large amounts of uninteresting coverage for every syscall.
The following snippets are sprinkled all over the place in kcov traces
in a debugging kernel. We already try to disable instrumentation of
stack unwinding code and of most debug facilities. I guess we did not
use fault-inject.c at the time, and stacktrace.c was somehow missed (or
something has changed in kernel/configs). This change both speeds up
kcov (kernel doesn't need to store these PCs, user-space doesn't need to
process them) and frees trace buffer capacity for more useful coverage.
should_fail
lib/fault-inject.c:149
fail_dump
lib/fault-inject.c:45
stack_trace_save
kernel/stacktrace.c:124
stack_trace_consume_entry
kernel/stacktrace.c:86
stack_trace_consume_entry
kernel/stacktrace.c:89
... a hundred frames skipped ...
stack_trace_consume_entry
kernel/stacktrace.c:93
stack_trace_consume_entry
kernel/stacktrace.c:86
Link: http://lkml.kernel.org/r/20200116111449.217744-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use PHYS_PFN() macro in io_mapping_map_atomic_wc() instead of open coded
variant.
Link: http://lkml.kernel.org/r/20191209165624.56351-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There were few episodes of silent downgrade to an executable stack over
years:
1) linking innocent looking assembly file will silently add executable
stack if proper linker options is not given as well:
$ cat f.S
.intel_syntax noprefix
.text
.globl f
f:
ret
$ cat main.c
void f(void);
int main(void)
{
f();
return 0;
}
$ gcc main.c f.S
$ readelf -l ./a.out
GNU_STACK 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x0000000000000000 0x0000000000000000 RWE 0x10
^^^
2) converting C99 nested function into a closure
https://nullprogram.com/blog/2019/11/15/
void intsort2(int *base, size_t nmemb, _Bool invert)
{
int cmp(const void *a, const void *b)
{
int r = *(int *)a - *(int *)b;
return invert ? -r : r;
}
qsort(base, nmemb, sizeof(*base), cmp);
}
will silently require stack trampolines while non-closure version will
not.
Without doubt this behaviour is documented somewhere, add a warning so
that developers and users can at least notice. After so many years of
x86_64 having proper executable stack support it should not cause too
many problems.
Link: http://lkml.kernel.org/r/20191208171918.GC19716@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Will Deacon <will@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable inode may be NULL in reiserfs_insert_item(), but there is
no check before accessing the member of inode.
Fix this by adding NULL pointer check before calling reiserfs_debug().
Link: http://lkml.kernel.org/r/79c5135d-ff25-1cc9-4e99-9f572b88cc00@huawei.com
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Hu Shiyuan <hushiyuan@huawei.com>
Cc: Feilong Lin <linfeilong@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This message leads to thinking that memory protection is not implemented
for the said architecture, whereas absence of CONFIG_STRICT_KERNEL_RWX
only means that memory protection has not been selected at compile time.
Don't print this message when CONFIG_ARCH_HAS_STRICT_KERNEL_RWX is
selected by the architecture. Instead, print "Kernel memory protection
not selected by kernel config."
Link: http://lkml.kernel.org/r/62477e446d9685459d4f27d193af6ff1bd69d55f.1578557581.git.christophe.leroy@c-s.fr
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "init/main.c: minor cleanup/bugfix of envvar handling", v2.
unknown_bootoption passes unrecognized command line arguments to init as
either environment variables or arguments. Some of the logic in the
function is broken for quoted command line arguments.
When an argument of the form param="value" is processed by parse_args
and passed to unknown_bootoption, the command line has
param\0"value\0
with val pointing to the beginning of value. The helper function
repair_env_string is then used to restore the '=' character that was
removed by parse_args, and strip the quotes off fully. This results in
param=value\0\0
and val ends up pointing to the 'a' instead of the 'v' in value. This
bug was introduced when repair_env_string was refactored into a separate
function, and the decrement of val in repair_env_string became dead
code.
This causes two problems in unknown_bootoption in the two places where
the val pointer is used as a substitute for the length of param:
1. An argument of the form param=".value" is misinterpreted as a
potential module parameter, with the result that it will not be
placed in init's environment.
2. An argument of the form param="value" is checked to see if param is
an existing environment variable that should be overwritten, but the
comparison is off-by-one and compares 'param=v' instead of 'param='
against the existing environment. So passing, for example,
TERM="vt100" on the command line results in init being passed both
TERM=linux and TERM=vt100 in its environment.
Patch 1 adds logging for the arguments and environment passed to init
and is independent of the rest: it can be dropped if this is
unnecessarily verbose.
Patch 2 removes repair_env_string from initcall parameter parsing in
do_initcall_level, as that uses a separate copy of the command line now
and the repairing is no longer necessary.
Patch 3 fixes the bug in unknown_bootoption by recording the length of
param explicitly instead of implying it from val-param.
This patch (of 3):
Commit a99cd11251 ("init: fix bug where environment vars can't be
passed via boot args") introduced two minor bugs in unknown_bootoption
by factoring out the quoted value handling into a separate function.
When value is quoted, repair_env_string will move the value up 1 byte to
strip the quotes, so val in unknown_bootoption no longer points to the
actual location of the value.
The result is that an argument of the form param=".value" is mistakenly
treated as a potential module parameter and is not placed in init's
environment, and an argument of the form param="value" can result in a
duplicate environment variable: eg TERM="vt100" on the command line will
result in both TERM=linux and TERM=vt100 being placed into init's
environment.
Fix this by recording the length of the param before calling
repair_env_string instead of relying on val.
Link: http://lkml.kernel.org/r/20191212180023.24339-4-nivedita@alum.mit.edu
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 08746a65c2 ("init: fix in-place parameter modification
regression"), parse_args in do_initcall_level is called on a copy of
saved_command_line. It is unnecessary to call repair_env_string during
this parsing, as this copy is not used for anything later.
Remove the now unnecessary arguments from repair_env_string as well.
Link: http://lkml.kernel.org/r/20191212180023.24339-3-nivedita@alum.mit.edu
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Krzysztof Mazur <krzysiek@podlesie.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extend logging in `run_init_process` to also show the arguments and
environment that we are passing to init.
Link: http://lkml.kernel.org/r/20191212180023.24339-2-nivedita@alum.mit.edu
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unmapping whole address space at once with
munmap(0, (1ULL<<47) - 4096)
or equivalent will create empty coredump.
It is silly way to exit, however registers content may still be useful.
The right to coredump is fundamental right of a process!
Link: http://lkml.kernel.org/r/20191222150137.GA1277@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Comment says ELF header is "too large to be on stack". 64 bytes on
64-bit is not large by any means.
Link: http://lkml.kernel.org/r/20191222143850.GA24341@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If some mapping goes past TASK_SIZE it will be rejected by kernel which
means no such userspace binaries exist.
Mark every such check as unlikely.
Link: http://lkml.kernel.org/r/20191215124355.GA21124@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"current->mm" pointer is stable in general except few cases one of which
execve(2). Compiler can't treat is as stable but it _is_ stable most of
the time. During ELF loading process ->mm becomes stable right after
flush_old_exec().
Help compiler by caching current->mm, otherwise it continues to refetch
it.
add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-141 (-141)
Function old new delta
elf_core_dump 5062 5039 -23
load_elf_binary 5426 5308 -118
Note: other cases are left as is because it is either pessimisation or
no change in binary size.
Link: http://lkml.kernel.org/r/20191215124755.GB21124@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ELF header is read into bprm->buf[] by generic execve code.
Save a memcpy and allocate just one header for the interpreter instead
of two headers (64 bytes instead of 128 on 64-bit).
Link: http://lkml.kernel.org/r/20191208171242.GA19716@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only executable segments should be accounted to ->start_code just like
they do to ->end_code (correctly).
Link: http://lkml.kernel.org/r/20191208171410.GB19716@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Filling auxv vector as array with index (auxv[i++] = ...) generates
terrible code. "saved_auxv" should be reworked because it is the worst
member of mm_struct by size/usefullness ratio but do it later.
Meanwhile help gcc a little with *auxv++ idiom.
Space savings on x86_64:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-127 (-127)
Function old new delta
load_elf_binary 5470 5343 -127
Link: http://lkml.kernel.org/r/20191208172301.GD19716@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It saves 25% of .text for arm64, and more for BE architectures.
Before:
$ size lib/find_bit.o
text data bss dec hex filename
1012 56 0 1068 42c lib/find_bit.o
After:
$ size lib/find_bit.o
text data bss dec hex filename
776 56 0 832 340 lib/find_bit.o
Link: http://lkml.kernel.org/r/20200103202846.21616-3-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Allison Randal <allison@lohutok.net>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
_find_next_bit and _find_next_bit_le are very similar functions. It's
possible to join them by adding 1 parameter and a couple of simple
checks. It's simplify maintenance and make possible to shrink the size
of .text by un-inlining the unified function (in the following patch).
Link: http://lkml.kernel.org/r/20200103202846.21616-2-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ext2_swab() is defined locally in lib/find_bit.c However it is not
specific to ext2, neither to bitmaps.
There are many potential users of it, so rename it to just swab() and
move to include/uapi/linux/swab.h
ABI guarantees that size of unsigned long corresponds to BITS_PER_LONG,
therefore drop unneeded cast.
Link: http://lkml.kernel.org/r/20200103202846.21616-1-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clang warns:
../lib/scatterlist.c:314:5: warning: misleading indentation; statement
is not part of the previous 'if' [-Wmisleading-indentation]
return -ENOMEM;
^
../lib/scatterlist.c:311:4: note: previous statement is here
if (prv)
^
1 warning generated.
This warning occurs because there is a space before the tab on this
line. Remove it so that the indentation is consistent with the Linux
kernel coding style and clang no longer warns.
Link: http://lkml.kernel.org/r/20191218033606.11942-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/830
Fixes: edce6820a9 ("scatterlist: prevent invalid free when alloc fails")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to benefit from s390 zlib hardware compression support,
increase the btrfs zlib workspace buffer size from 1 to 4 pages (if s390
zlib hardware support is enabled on the machine).
This brings up to 60% better performance in hardware on s390 compared to
the PAGE_SIZE buffer and much more compared to the software zlib
processing in btrfs. In case of memory pressure, fall back to a single
page buffer during workspace allocation.
The data compressed with larger input buffers will still conform to zlib
standard and thus can be decompressed also on a systems that uses only
PAGE_SIZE buffer for btrfs zlib.
Link: http://lkml.kernel.org/r/20200108105103.29028-1-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new function to zlib.h checking if s390 Deflate-Conversion
facility is installed and enabled.
Link: http://lkml.kernel.org/r/20200103223334.20669-6-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the new kernel command line parameter 'dfltcc=' to configure s390
zlib hardware support.
Format: { on | off | def_only | inf_only | always }
on: s390 zlib hardware support for compression on
level 1 and decompression (default)
off: No s390 zlib hardware support
def_only: s390 zlib hardware support for deflate
only (compression on level 1)
inf_only: s390 zlib hardware support for inflate
only (decompression)
always: Same as 'on' but ignores the selected compression
level always using hardware support (used for debugging)
Link: http://lkml.kernel.org/r/20200103223334.20669-5-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the conflicting macro name in preparation for zlib_inflate
hardware support.
Link: http://lkml.kernel.org/r/20200103223334.20669-3-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "S390 hardware support for kernel zlib", v3.
With IBM z15 mainframe the new DFLTCC instruction is available. It
implements deflate algorithm in hardware (Nest Acceleration Unit - NXU)
with estimated compression and decompression performance orders of
magnitude faster than the current zlib.
This patchset adds s390 hardware compression support to kernel zlib.
The code is based on the userspace zlib implementation:
https://github.com/madler/zlib/pull/410
The coding style is also preserved for future maintainability. There is
only limited set of userspace zlib functions represented in kernel.
Apart from that, all the memory allocation should be performed in
advance. Thus, the workarea structures are extended with the parameter
lists required for the DEFLATE CONVENTION CALL instruction.
Since kernel zlib itself does not support gzip headers, only Adler-32
checksum is processed (also can be produced by DFLTCC facility). Like
it was implemented for userspace, kernel zlib will compress in hardware
on level 1, and in software on all other levels. Decompression will
always happen in hardware (when enabled).
Two DFLTCC compression calls produce the same results only when they
both are made on machines of the same generation, and when the
respective buffers have the same offset relative to the start of the
page. Therefore care should be taken when using hardware compression
when reproducible results are desired. However it does always produce
the standard conform output which can be inflated anyway.
The new kernel command line parameter 'dfltcc' is introduced to
configure s390 zlib hardware support:
Format: { on | off | def_only | inf_only | always }
on: s390 zlib hardware support for compression on
level 1 and decompression (default)
off: No s390 zlib hardware support
def_only: s390 zlib hardware support for deflate
only (compression on level 1)
inf_only: s390 zlib hardware support for inflate
only (decompression)
always: Same as 'on' but ignores the selected compression
level always using hardware support (used for debugging)
The main purpose of the integration of the NXU support into the kernel
zlib is the use of hardware deflate in btrfs filesystem with on-the-fly
compression enabled. Apart from that, hardware support can also be used
during boot for decompressing the kernel or the ramdisk image
With the patch for btrfs expanding zlib buffer from 1 to 4 pages (patch
6) the following performance results have been achieved using the
ramdisk with btrfs. These are relative numbers based on throughput rate
and compression ratio for zlib level 1:
Input data Deflate rate Inflate rate Compression ratio
NXU/Software NXU/Software NXU/Software
stream of zeroes 1.46 1.02 1.00
random ASCII data 10.44 3.00 0.96
ASCII text (dickens) 6,21 3.33 0.94
binary data (vmlinux) 8,37 3.90 1.02
This means that s390 hardware deflate can provide up to 10 times faster
compression (on level 1) and up to 4 times faster decompression (refers
to all compression levels) for btrfs zlib.
Disclaimer: Performance results are based on IBM internal tests using DD
command-line utility on btrfs on a Fedora 30 based internal driver in
native LPAR on a z15 system. Results may vary based on individual
workload, configuration and software levels.
This patch (of 9):
Create zlib_dfltcc library with the s390 DEFLATE CONVERSION CALL
implementation and related compression functions. Update zlib_deflate
functions with the hooks for s390 hardware support and adjust workspace
structures with extra parameter lists required for hardware deflate.
Link: http://lkml.kernel.org/r/20200103223334.20669-2-zaslonko@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Co-developed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
