Revision tags: v6.6.67, v6.6.66, v6.6.65, v6.6.64, v6.6.63, v6.6.62, v6.6.61, v6.6.60, v6.6.59, v6.6.58, v6.6.57, v6.6.56, v6.6.55, v6.6.54, v6.6.53, v6.6.52, v6.6.51, v6.6.50, v6.6.49, v6.6.48, v6.6.47 |
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c005e2f6 |
| 14-Aug-2024 |
Andrew Jeffery <andrew@codeconstruct.com.au> |
Merge tag 'v6.6.46' into for/openbmc/dev-6.6
This is the 6.6.46 stable release
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Revision tags: v6.6.46, v6.6.45 |
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81ac1e88 |
| 09-Aug-2024 |
Linus Torvalds <torvalds@linux-foundation.org> |
module: make waiting for a concurrent module loader interruptible
[ Upstream commit 2124d84db293ba164059077944e6b429ba530495 ]
The recursive aes-arm-bs module load situation reported by Russell Kin
module: make waiting for a concurrent module loader interruptible
[ Upstream commit 2124d84db293ba164059077944e6b429ba530495 ]
The recursive aes-arm-bs module load situation reported by Russell King is getting fixed in the crypto layer, but this in the meantime fixes the "recursive load hangs forever" by just making the waiting for the first module load be interruptible.
This should now match the old behavior before commit 9b9879fc0327 ("modules: catch concurrent module loads, treat them as idempotent"), which used the different "wait for module to be ready" code in module_patient_check_exists().
End result: a recursive module load will still block, but now a signal will interrupt it and fail the second module load, at which point the first module will successfully complete loading.
Fixes: 9b9879fc0327 ("modules: catch concurrent module loads, treat them as idempotent") Cc: Russell King <linux@armlinux.org.uk> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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bdb3679c |
| 08-Aug-2024 |
Linus Torvalds <torvalds@linux-foundation.org> |
module: warn about excessively long module waits
[ Upstream commit cb5b81bc9a448f8db817566f60f92e2ea788ea0f ]
Russell King reported that the arm cbc(aes) crypto module hangs when loaded, and Herber
module: warn about excessively long module waits
[ Upstream commit cb5b81bc9a448f8db817566f60f92e2ea788ea0f ]
Russell King reported that the arm cbc(aes) crypto module hangs when loaded, and Herbert Xu bisected it to commit 9b9879fc0327 ("modules: catch concurrent module loads, treat them as idempotent"), and noted:
"So what's happening here is that the first modprobe tries to load a fallback CBC implementation, in doing so it triggers a load of the exact same module due to module aliases.
IOW we're loading aes-arm-bs which provides cbc(aes). However, this needs a fallback of cbc(aes) to operate, which is made out of the generic cbc module + any implementation of aes, or ecb(aes). The latter happens to also be provided by aes-arm-cb so that's why it tries to load the same module again"
So loading the aes-arm-bs module ends up wanting to recursively load itself, and the recursive load then ends up waiting for the original module load to complete.
This is a regression, in that it used to be that we just tried to load the module multiple times, and then as we went on to install it the second time we would instead just error out because the module name already existed.
That is actually also exactly what the original "catch concurrent loads" patch did in commit 9828ed3f695a ("module: error out early on concurrent load of the same module file"), but it turns out that it ends up being racy, in that erroring out before the module has been fully initialized will cause failures in dependent module loading.
See commit ac2263b588df (which was the revert of that "error out early") commit for details about why erroring out before the module has been initialized is actually fundamentally racy.
Now, for the actual recursive module load (as opposed to just concurrently loading the same module twice), the race is not an issue.
At the same time it's hard for the kernel to see that this is recursion, because the module load is always done from a usermode helper, so the recursion is not some simple callchain within the kernel.
End result: this is not the real fix, but this at least adds a warning for the situation (admittedly much too late for all the debugging pain that Russell and Herbert went through) and if we can come to a resolution on how to detect the recursion properly, this re-organizes the code to make that easier.
Link: https://lore.kernel.org/all/ZrFHLqvFqhzykuYw@shell.armlinux.org.uk/ Reported-by: Russell King <linux@armlinux.org.uk> Debugged-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Stable-dep-of: 2124d84db293 ("module: make waiting for a concurrent module loader interruptible") Signed-off-by: Sasha Levin <sashal@kernel.org>
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Revision tags: v6.6.44, v6.6.43, v6.6.42, v6.6.41, v6.6.40, v6.6.39, v6.6.38, v6.6.37, v6.6.36, v6.6.35, v6.6.34, v6.6.33, v6.6.32, v6.6.31, v6.6.30, v6.6.29, v6.6.28, v6.6.27, v6.6.26, v6.6.25, v6.6.24 |
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5ee9cd06 |
| 27-Mar-2024 |
Andrew Jeffery <andrew@codeconstruct.com.au> |
Merge tag 'v6.6.23' into dev-6.6
Linux 6.6.23
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Revision tags: v6.6.23 |
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8c61e3be |
| 26-Feb-2024 |
Changbin Du <changbin.du@huawei.com> |
modules: wait do_free_init correctly
[ Upstream commit 8f8cd6c0a43ed637e620bbe45a8d0e0c2f4d5130 ]
The synchronization here is to ensure the ordering of freeing of a module init so that it happens b
modules: wait do_free_init correctly
[ Upstream commit 8f8cd6c0a43ed637e620bbe45a8d0e0c2f4d5130 ]
The synchronization here is to ensure the ordering of freeing of a module init so that it happens before W+X checking. It is worth noting it is not that the freeing was not happening, it is just that our sanity checkers raced against the permission checkers which assume init memory is already gone.
Commit 1a7b7d922081 ("modules: Use vmalloc special flag") moved calling do_free_init() into a global workqueue instead of relying on it being called through call_rcu(..., do_free_init), which used to allowed us call do_free_init() asynchronously after the end of a subsequent grace period. The move to a global workqueue broke the gaurantees for code which needed to be sure the do_free_init() would complete with rcu_barrier(). To fix this callers which used to rely on rcu_barrier() must now instead use flush_work(&init_free_wq).
Without this fix, we still could encounter false positive reports in W+X checking since the rcu_barrier() here can not ensure the ordering now.
Even worse, the rcu_barrier() can introduce significant delay. Eric Chanudet reported that the rcu_barrier introduces ~0.1s delay on a PREEMPT_RT kernel.
[ 0.291444] Freeing unused kernel memory: 5568K [ 0.402442] Run /sbin/init as init process
With this fix, the above delay can be eliminated.
Link: https://lkml.kernel.org/r/20240227023546.2490667-1-changbin.du@huawei.com Fixes: 1a7b7d922081 ("modules: Use vmalloc special flag") Signed-off-by: Changbin Du <changbin.du@huawei.com> Tested-by: Eric Chanudet <echanude@redhat.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Xiaoyi Su <suxiaoyi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Revision tags: v6.6.16, v6.6.15, v6.6.14, v6.6.13, v6.6.12, v6.6.11, v6.6.10, v6.6.9, v6.6.8, v6.6.7, v6.6.6, v6.6.5, v6.6.4, v6.6.3, v6.6.2, v6.5.11, v6.6.1, v6.5.10, v6.6, v6.5.9, v6.5.8, v6.5.7, v6.5.6, v6.5.5, v6.5.4, v6.5.3 |
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c900529f |
| 12-Sep-2023 |
Thomas Zimmermann <tzimmermann@suse.de> |
Merge drm/drm-fixes into drm-misc-fixes
Forwarding to v6.6-rc1.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
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Revision tags: v6.5.2, v6.1.51, v6.5.1 |
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1ac731c5 |
| 30-Aug-2023 |
Dmitry Torokhov <dmitry.torokhov@gmail.com> |
Merge branch 'next' into for-linus
Prepare input updates for 6.6 merge window.
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Revision tags: v6.1.50 |
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daa22f5a |
| 29-Aug-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
Merge tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull modules updates from Luis Chamberlain: "Summary of the changes worth highlighting from most interestin
Merge tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull modules updates from Luis Chamberlain: "Summary of the changes worth highlighting from most interesting to boring below:
- Christoph Hellwig's symbol_get() fix to Nvidia's efforts to circumvent the protection he put in place in year 2020 to prevent proprietary modules from using GPL only symbols, and also ensuring proprietary modules which export symbols grandfather their taint.
That was done through year 2020 commit 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE"). Christoph's new fix is done by clarifing __symbol_get() was only ever intended to prevent module reference loops by Linux kernel modules and so making it only find symbols exported via EXPORT_SYMBOL_GPL(). The circumvention tactic used by Nvidia was to use symbol_get() to purposely swift through proprietary module symbols and completely bypass our traditional EXPORT_SYMBOL*() annotations and community agreed upon restrictions.
A small set of preamble patches fix up a few symbols which just needed adjusting for this on two modules, the rtc ds1685 and the networking enetc module. Two other modules just needed some build fixing and removal of use of __symbol_get() as they can't ever be modular, as was done by Arnd on the ARM pxa module and Christoph did on the mmc au1xmmc driver.
This is a good reminder to us that symbol_get() is just a hack to address things which should be fixed through Kconfig at build time as was done in the later patches, and so ultimately it should just go.
- Extremely late minor fix for old module layout 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()") by James Morse for arm64. Note that this layout thing is old, it is *not* Song Liu's commit ac3b43283923 ("module: replace module_layout with module_memory"). The issue however is very odd to run into and so there was no hurry to get this in fast.
- Although the fix did not go through the modules tree I'd like to highlight the fix by Peter Zijlstra in commit 54097309620e ("x86/static_call: Fix __static_call_fixup()") now merged in your tree which came out of what was originally suspected to be a fallout of the the newer module layout changes by Song Liu commit ac3b43283923 ("module: replace module_layout with module_memory") instead of module_init_section()"). Thanks to the report by Christian Bricart and the debugging by Song Liu & Peter that turned to be noted as a kernel regression in place since v5.19 through commit ee88d363d156 ("x86,static_call: Use alternative RET encoding").
I highlight this to reflect and clarify that we haven't seen more fallout from ac3b43283923 ("module: replace module_layout with module_memory").
- RISC-V toolchain got mapping symbol support which prefix symbols with "$" to help with alignment considerations for disassembly.
This is used to differentiate between incompatible instruction encodings when disassembling. RISC-V just matches what ARM/AARCH64 did for alignment considerations and Palmer Dabbelt extended is_mapping_symbol() to accept these symbols for RISC-V. We already had support for this for all architectures but it also checked for the second character, the RISC-V check Dabbelt added was just for the "$". After a bit of testing and fallout on linux-next and based on feedback from Masahiro Yamada it was decided to simplify the check and treat the first char "$" as unique for all architectures, and so we no make is_mapping_symbol() for all archs if the symbol starts with "$".
The most relevant commit for this for RISC-V on binutils was:
https://sourceware.org/pipermail/binutils/2021-July/117350.html
- A late fix by Andrea Righi (today) to make module zstd decompression use vmalloc() instead of kmalloc() to account for large compressed modules. I suspect we'll see similar things for other decompression algorithms soon.
- samples/hw_breakpoint minor fixes by Rong Tao, Arnd Bergmann and Chen Jiahao"
* tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: module/decompress: use vmalloc() for zstd decompression workspace kallsyms: Add more debug output for selftest ARM: module: Use module_init_layout_section() to spot init sections arm64: module: Use module_init_layout_section() to spot init sections module: Expose module_init_layout_section() modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules rtc: ds1685: use EXPORT_SYMBOL_GPL for ds1685_rtc_poweroff net: enetc: use EXPORT_SYMBOL_GPL for enetc_phc_index mmc: au1xmmc: force non-modular build and remove symbol_get usage ARM: pxa: remove use of symbol_get() samples/hw_breakpoint: mark sample_hbp as static samples/hw_breakpoint: fix building without module unloading samples/hw_breakpoint: Fix kernel BUG 'invalid opcode: 0000' modpost, kallsyms: Treat add '$'-prefixed symbols as mapping symbols kernel: params: Remove unnecessary ‘0’ values from err module: Ignore RISC-V mapping symbols too
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Revision tags: v6.5, v6.1.49, v6.1.48, v6.1.46, v6.1.45, v6.1.44 |
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2612e3bb |
| 07-Aug-2023 |
Rodrigo Vivi <rodrigo.vivi@intel.com> |
Merge drm/drm-next into drm-intel-next
Catching-up with drm-next and drm-intel-gt-next. It will unblock a code refactor around the platform definitions (names vs acronyms).
Signed-off-by: Rodrigo V
Merge drm/drm-next into drm-intel-next
Catching-up with drm-next and drm-intel-gt-next. It will unblock a code refactor around the platform definitions (names vs acronyms).
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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9f771739 |
| 07-Aug-2023 |
Joonas Lahtinen <joonas.lahtinen@linux.intel.com> |
Merge drm/drm-next into drm-intel-gt-next
Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as a dependency for https://patchwork.freedesktop.org/series/1
Merge drm/drm-next into drm-intel-gt-next
Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as a dependency for https://patchwork.freedesktop.org/series/121735/
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
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Revision tags: v6.1.43 |
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2abcc4b5 |
| 01-Aug-2023 |
James Morse <james.morse@arm.com> |
module: Expose module_init_layout_section()
module_init_layout_section() choses whether the core module loader considers a section as init or not. This affects the placement of the exit section when
module: Expose module_init_layout_section()
module_init_layout_section() choses whether the core module loader considers a section as init or not. This affects the placement of the exit section when module unloading is disabled. This code will never run, so it can be free()d once the module has been initialised.
arm and arm64 need to count the number of PLTs they need before applying relocations based on the section name. The init PLTs are stored separately so they can be free()d. arm and arm64 both use within_module_init() to decide which list of PLTs to use when applying the relocation.
Because within_module_init()'s behaviour changes when module unloading is disabled, both architecture would need to take this into account when counting the PLTs.
Today neither architecture does this, meaning when module unloading is disabled there are insufficient PLTs in the init section to load some modules, resulting in warnings: | WARNING: CPU: 2 PID: 51 at arch/arm64/kernel/module-plts.c:99 module_emit_plt_entry+0x184/0x1cc | Modules linked in: crct10dif_common | CPU: 2 PID: 51 Comm: modprobe Not tainted 6.5.0-rc4-yocto-standard-dirty #15208 | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : module_emit_plt_entry+0x184/0x1cc | lr : module_emit_plt_entry+0x94/0x1cc | sp : ffffffc0803bba60 [...] | Call trace: | module_emit_plt_entry+0x184/0x1cc | apply_relocate_add+0x2bc/0x8e4 | load_module+0xe34/0x1bd4 | init_module_from_file+0x84/0xc0 | __arm64_sys_finit_module+0x1b8/0x27c | invoke_syscall.constprop.0+0x5c/0x104 | do_el0_svc+0x58/0x160 | el0_svc+0x38/0x110 | el0t_64_sync_handler+0xc0/0xc4 | el0t_64_sync+0x190/0x194
Instead of duplicating module_init_layout_section()s logic, expose it.
Reported-by: Adam Johnston <adam.johnston@arm.com> Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()") Cc: stable@vger.kernel.org Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
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9011e49d |
| 01-Aug-2023 |
Christoph Hellwig <hch@lst.de> |
modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules
It has recently come to my attention that nvidia is circumventing the protection added in 262e6ae7081d ("modules: inherit TAINT_PROPRIETAR
modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules
It has recently come to my attention that nvidia is circumventing the protection added in 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE") by importing exports from their proprietary modules into an allegedly GPL licensed module and then rexporting them.
Given that symbol_get was only ever intended for tightly cooperating modules using very internal symbols it is logical to restrict it to being used on EXPORT_SYMBOL_GPL and prevent nvidia from costly DMCA Circumvention of Access Controls law suites.
All symbols except for four used through symbol_get were already exported as EXPORT_SYMBOL_GPL, and the remaining four ones were switched over in the preparation patches.
Fixes: 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
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Revision tags: v6.1.42, v6.1.41 |
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61b73694 |
| 24-Jul-2023 |
Thomas Zimmermann <tzimmermann@suse.de> |
Merge drm/drm-next into drm-misc-next
Backmerging to get v6.5-rc2.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
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Revision tags: v6.1.40, v6.1.39 |
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50501936 |
| 17-Jul-2023 |
Dmitry Torokhov <dmitry.torokhov@gmail.com> |
Merge tag 'v6.4' into next
Sync up with mainline to bring in updates to shared infrastructure.
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0791faeb |
| 17-Jul-2023 |
Mark Brown <broonie@kernel.org> |
ASoC: Merge v6.5-rc2
Get a similar baseline to my other branches, and fixes for people using the branch.
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2f98e686 |
| 11-Jul-2023 |
Maxime Ripard <mripard@kernel.org> |
Merge v6.5-rc1 into drm-misc-fixes
Boris needs 6.5-rc1 in drm-misc-fixes to prevent a conflict.
Signed-off-by: Maxime Ripard <mripard@kernel.org>
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Revision tags: v6.1.38 |
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f1962207 |
| 04-Jul-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
module: fix init_module_from_file() error handling
Vegard Nossum pointed out two different problems with the error handling in init_module_from_file():
(a) the idempotent loading code didn't clean
module: fix init_module_from_file() error handling
Vegard Nossum pointed out two different problems with the error handling in init_module_from_file():
(a) the idempotent loading code didn't clean up properly in some error cases, leaving the on-stack 'struct idempotent' element still in the hash table
(b) failure to read the module file would nonsensically update the 'invalid_kread_bytes' stat counter with the error value
The first error is quite nasty, in that it can then cause subsequent idempotent loads of that same file to access stale stack contents of the previous failure. The case may not happen in any normal situation (explaining all the "Tested-by's on the original change), and requires admin privileges, but syzkaller triggers random bad behavior as a result:
BUG: soft lockup in sys_finit_module BUG: unable to handle kernel paging request in init_module_from_file general protection fault in init_module_from_file INFO: task hung in init_module_from_file KASAN: out-of-bounds Read in init_module_from_file KASAN: slab-out-of-bounds Read in init_module_from_file ...
The second error is fairly benign and just leads to nonsensical stats (and has been around since the debug stats were added).
Vegard also provided a patch for the idempotent loading issue, but I'd rather re-organize the code and make it more legible using another level of helper functions than add the usual "goto out" error handling.
Link: https://lore.kernel.org/lkml/20230704100852.23452-1-vegard.nossum@oracle.com/ Fixes: 9b9879fc0327 ("modules: catch concurrent module loads, treat them as idempotent") Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Reported-by: syzbot+9c2bdc9d24e4a7abe741@syzkaller.appspotmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Revision tags: v6.1.37 |
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44f10dbe |
| 30-Jun-2023 |
Andrew Morton <akpm@linux-foundation.org> |
Merge branch 'master' into mm-hotfixes-stable
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0a30901b |
| 30-Jun-2023 |
Andrew Morton <akpm@linux-foundation.org> |
Merge branch 'master' into mm-hotfixes-stable
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4e3c09e9 |
| 28-Jun-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
Merge tag 'v6.5-rc1-modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull module updates from Luis Chamberlain: "The changes queued up for modules are pretty tame, mostly
Merge tag 'v6.5-rc1-modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull module updates from Luis Chamberlain: "The changes queued up for modules are pretty tame, mostly code removal of moving of code.
Only two minor functional changes are made, the only one which stands out is Sebastian Andrzej Siewior's simplification of module reference counting by removing preempt_disable() and that has been tested on linux-next for well over a month without no regressions.
I'm now, I guess, also a kitchen sink for some kallsyms changes"
[ There was a mis-communication about the concurrent module load changes that I had expected to come through Luis despite me authoring the patch. So some of the module updates were left hanging in the email ether, and I just committed them separately.
It's my bad - I should have made it more clear that I expected my own patches to come through the module tree too. Now they missed linux-next, but hopefully that won't cause any issues - Linus ]
* tag 'v6.5-rc1-modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: kallsyms: make kallsyms_show_value() as generic function kallsyms: move kallsyms_show_value() out of kallsyms.c kallsyms: remove unsed API lookup_symbol_attrs kallsyms: remove unused arch_get_kallsym() helper module: Remove preempt_disable() from module reference counting.
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Revision tags: v6.1.36, v6.4, v6.1.35, v6.1.34, v6.1.33, v6.1.32, v6.1.31 |
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9b9879fc |
| 29-May-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
modules: catch concurrent module loads, treat them as idempotent
This is the new-and-improved attempt at avoiding huge memory load spikes when the user space boot sequence tries to load hundreds (or
modules: catch concurrent module loads, treat them as idempotent
This is the new-and-improved attempt at avoiding huge memory load spikes when the user space boot sequence tries to load hundreds (or even thousands) of redundant duplicate modules in parallel.
See commit 9828ed3f695a ("module: error out early on concurrent load of the same module file") for background and an earlier failed attempt that was reverted.
That earlier attempt just said "concurrently loading the same module is silly, just open the module file exclusively and return -ETXTBSY if somebody else is already loading it".
While it is true that concurrent module loads of the same module is silly, the reason that earlier attempt then failed was that the concurrently loaded module would often be a prerequisite for another module.
Thus failing to load the prerequisite would then cause cascading failures of the other modules, rather than just short-circuiting that one unnecessary module load.
At the same time, we still really don't want to load the contents of the same module file hundreds of times, only to then wait for an eventually successful load, and have everybody else return -EEXIST.
As a result, this takes another approach, and treats concurrent module loads from the same file as "idempotent" in the inode. So if one module load is ongoing, we don't start a new one, but instead just wait for the first one to complete and return the same return value as it did.
So unlike the first attempt, this does not return early: the intent is not to speed up the boot, but to avoid a thundering herd problem in allocating memory (both physical and virtual) for a module more than once.
Also note that this does change behavior: it used to be that when you had concurrent loads, you'd have one "winner" that would return success, and everybody else would return -EEXIST.
In contrast, this idempotent logic goes all Oprah on the problem, and says "You are a winner! And you are a winner! We are ALL winners". But since there's no possible actual real semantic difference between "you loaded the module" and "somebody else already loaded the module", this is more of a feel-good change than an actual honest-to-goodness semantic change.
Of course, any true Johnny-come-latelies that don't get caught in the concurrency filter will still return -EEXIST. It's no different from not even getting a seat at an Oprah taping. That's life.
See the long thread on the kernel mailing list about this all, which includes some numbers for memory use before and after the patch.
Link: https://lore.kernel.org/lkml/20230524213620.3509138-1-mcgrof@kernel.org/ Reviewed-by: Johan Hovold <johan@kernel.org> Tested-by: Johan Hovold <johan@kernel.org> Tested-by: Luis Chamberlain <mcgrof@kernel.org> Tested-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Rudi Heitbaum <rudi@heitbaum..com> Tested-by: David Hildenbrand <david@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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054a7300 |
| 29-May-2023 |
Linus Torvalds <torvalds@linux-foundation.org> |
module: split up 'finit_module()' into init_module_from_file() helper
This will simplify the next step, where we can then key off the inode to do one idempotent module load.
Let's do the obvious re
module: split up 'finit_module()' into init_module_from_file() helper
This will simplify the next step, where we can then key off the inode to do one idempotent module load.
Let's do the obvious re-organization in one step, and then the new code in another.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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e80b5003 |
| 27-Jun-2023 |
Jiri Kosina <jkosina@suse.cz> |
Merge branch 'for-6.5/apple' into for-linus
- improved support for Keychron K8 keyboard (Lasse Brun)
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5f004bca |
| 27-Jun-2023 |
Jason Gunthorpe <jgg@nvidia.com> |
Merge tag 'v6.4' into rdma.git for-next
Linux 6.4
Resolve conflicts between rdma rc and next in rxe_cq matching linux-next:
drivers/infiniband/sw/rxe/rxe_cq.c: https://lore.kernel.org/r/20230622
Merge tag 'v6.4' into rdma.git for-next
Linux 6.4
Resolve conflicts between rdma rc and next in rxe_cq matching linux-next:
drivers/infiniband/sw/rxe/rxe_cq.c: https://lore.kernel.org/r/20230622115246.365d30ad@canb.auug.org.au
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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f121ab7f |
| 26-Jun-2023 |
Thomas Gleixner <tglx@linutronix.de> |
Merge tag 'irqchip-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- A number of Loogson/Loogarch fixes
- Allow th
Merge tag 'irqchip-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- A number of Loogson/Loogarch fixes
- Allow the core code to retrigger an interrupt that has fired while the same interrupt is being handled on another CPU, papering over a GICv3 architecture issue
- Work around an integration problem on ASR8601, where the CPU numbering isn't representable in the GIC implementation...
- Add some missing interrupt to the STM32 irqchip
- A bunch of warning squashing triggered by W=1 builds
Link: https://lore.kernel.org/r/20230623224345.3577134-1-maz@kernel.org
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