linux-stable.git/arch/mips/kernel, branch v6.6.26 Linux kernel stable tree MIPS: reserve exception vector space ONLY ONCE 2024-03-01T12:34:50+00:00 Huang Pei huangpei@loongson.cn 2024-01-23T01:47:57+00:00 f778a45784d34355b481b16b8348374fa2e585eb [ Upstream commit abcabb9e30a1f9a69c76776f8abffc31c377b542 ] "cpu_probe" is called both by BP and APs, but reserving exception vector (like 0x0-0x1000) called by "cpu_probe" need once and calling on APs is too late since memblock is unavailable at that time. So, reserve exception vector ONLY by BP. Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Huang Pei <huangpei@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit abcabb9e30a1f9a69c76776f8abffc31c377b542 ]

"cpu_probe" is called both by BP and APs, but reserving exception vector
(like 0x0-0x1000) called by "cpu_probe" need once and calling on APs is
too late since memblock is unavailable at that time.

So, reserve exception vector ONLY by BP.

Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Huang Pei <huangpei@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ptrace: Introduce exception_ip arch hook 2024-02-23T08:24:53+00:00 Jiaxun Yang jiaxun.yang@flygoat.com 2024-02-02T12:30:26+00:00 fdd12a80f64fbe68307619f3e83ed17e12118de3 [ Upstream commit 11ba1728be3edb6928791f4c622f154ebe228ae6 ] On architectures with delay slot, architecture level instruction pointer (or program counter) in pt_regs may differ from where exception was triggered. Introduce exception_ip hook to invoke architecture code and determine actual instruction pointer to the exception. Link: https://lore.kernel.org/lkml/00d1b813-c55f-4365-8d81-d70258e10b16@app.fastmail.com/ Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Stable-dep-of: 8fa507083388 ("mm/memory: Use exception ip to search exception tables") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 11ba1728be3edb6928791f4c622f154ebe228ae6 ]

On architectures with delay slot, architecture level instruction
pointer (or program counter) in pt_regs may differ from where
exception was triggered.

Introduce exception_ip hook to invoke architecture code and determine
actual instruction pointer to the exception.

Link: https://lore.kernel.org/lkml/00d1b813-c55f-4365-8d81-d70258e10b16@app.fastmail.com/
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Stable-dep-of: 8fa507083388 ("mm/memory: Use exception ip to search exception tables")
Signed-off-by: Sasha Levin <sashal@kernel.org>
mips: Call lose_fpu(0) before initializing fcr31 in mips_set_personality_nan 2024-02-01T00:19:13+00:00 Xi Ruoyao xry111@xry111.site 2024-01-26T21:05:57+00:00 33f49a68352dcd15b7b32ee5c3e954cad7bb21f6 commit 59be5c35850171e307ca5d3d703ee9ff4096b948 upstream. If we still own the FPU after initializing fcr31, when we are preempted the dirty value in the FPU will be read out and stored into fcr31, clobbering our setting. This can cause an improper floating-point environment after execve(). For example: zsh% cat measure.c #include <fenv.h> int main() { return fetestexcept(FE_INEXACT); } zsh% cc measure.c -o measure -lm zsh% echo $((1.0/3)) # raising FE_INEXACT 0.33333333333333331 zsh% while ./measure; do ; done (stopped in seconds) Call lose_fpu(0) before setting fcr31 to prevent this. Closes: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/ Fixes: 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling") Cc: stable@vger.kernel.org Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 59be5c35850171e307ca5d3d703ee9ff4096b948 upstream.

If we still own the FPU after initializing fcr31, when we are preempted
the dirty value in the FPU will be read out and stored into fcr31,
clobbering our setting.  This can cause an improper floating-point
environment after execve().  For example:

    zsh% cat measure.c
    #include <fenv.h>
    int main() { return fetestexcept(FE_INEXACT); }
    zsh% cc measure.c -o measure -lm
    zsh% echo $((1.0/3)) # raising FE_INEXACT
    0.33333333333333331
    zsh% while ./measure; do ; done
    (stopped in seconds)

Call lose_fpu(0) before setting fcr31 to prevent this.

Closes: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/
Fixes: 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling")
Cc: stable@vger.kernel.org
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mips: Fix incorrect max_low_pfn adjustment 2024-01-25T23:35:49+00:00 Serge Semin fancer.lancer@gmail.com 2023-12-02T11:14:19+00:00 66c8b147fe04f7dae18e8367d2fc67cbc02f77ee [ Upstream commit 0f5cc249ff73552d3bd864e62f85841dafaa107d ] max_low_pfn variable is incorrectly adjusted if the kernel is built with high memory support and the later is detected in a running system, so the memory which actually can be directly mapped is getting into the highmem zone. See the ZONE_NORMAL range on my MIPS32r5 system: > Zone ranges: > DMA [mem 0x0000000000000000-0x0000000000ffffff] > Normal [mem 0x0000000001000000-0x0000000007ffffff] > HighMem [mem 0x0000000008000000-0x000000020fffffff] while the zones are supposed to look as follows: > Zone ranges: > DMA [mem 0x0000000000000000-0x0000000000ffffff] > Normal [mem 0x0000000001000000-0x000000001fffffff] > HighMem [mem 0x0000000020000000-0x000000020fffffff] Even though the physical memory within the range [0x08000000;0x20000000] belongs to MMIO on our system, we don't really want it to be considered as high memory since on MIPS32 that range still can be directly mapped. Note there might be other problems caused by the max_low_pfn variable misconfiguration. For instance high_memory variable is initialize with virtual address corresponding to the max_low_pfn PFN, and by design it must define the upper bound on direct map memory, then end of the normal zone. That in its turn potentially may cause problems in accessing the memory by means of the /dev/mem and /dev/kmem devices. Let's fix the discovered misconfiguration then. It turns out the commit a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") didn't introduce the max_low_pfn adjustment quite correct. If the kernel is built with high memory support and the system is equipped with high memory, the max_low_pfn variable will need to be initialized with PFN of the most upper directly reachable memory address so the zone normal would be correctly setup. On MIPS that PFN corresponds to PFN_DOWN(HIGHMEM_START). If the system is built with no high memory support and one is detected in the running system, we'll just need to adjust the max_pfn variable to discard the found high memory from the system and leave the max_low_pfn as is, since the later will be less than PFN_DOWN(HIGHMEM_START) anyway by design of the for_each_memblock() loop performed a bit early in the bootmem_init() method. Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") Signed-off-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0f5cc249ff73552d3bd864e62f85841dafaa107d ]

max_low_pfn variable is incorrectly adjusted if the kernel is built with
high memory support and the later is detected in a running system, so the
memory which actually can be directly mapped is getting into the highmem
zone. See the ZONE_NORMAL range on my MIPS32r5 system:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x0000000007ffffff]
>   HighMem  [mem 0x0000000008000000-0x000000020fffffff]

while the zones are supposed to look as follows:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x000000001fffffff]
>   HighMem  [mem 0x0000000020000000-0x000000020fffffff]

Even though the physical memory within the range [0x08000000;0x20000000]
belongs to MMIO on our system, we don't really want it to be considered as
high memory since on MIPS32 that range still can be directly mapped.

Note there might be other problems caused by the max_low_pfn variable
misconfiguration. For instance high_memory variable is initialize with
virtual address corresponding to the max_low_pfn PFN, and by design it
must define the upper bound on direct map memory, then end of the normal
zone. That in its turn potentially may cause problems in accessing the
memory by means of the /dev/mem and /dev/kmem devices.

Let's fix the discovered misconfiguration then. It turns out the commit
a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") didn't introduce the
max_low_pfn adjustment quite correct. If the kernel is built with high
memory support and the system is equipped with high memory, the
max_low_pfn variable will need to be initialized with PFN of the most
upper directly reachable memory address so the zone normal would be
correctly setup. On MIPS that PFN corresponds to PFN_DOWN(HIGHMEM_START).
If the system is built with no high memory support and one is detected in
the running system, we'll just need to adjust the max_pfn variable to
discard the found high memory from the system and leave the max_low_pfn as
is, since the later will be less than PFN_DOWN(HIGHMEM_START) anyway by
design of the for_each_memblock() loop performed a bit early in the
bootmem_init() method.

Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
mips/smp: Call rcutree_report_cpu_starting() earlier 2024-01-25T23:35:41+00:00 Stefan Wiehler stefan.wiehler@nokia.com 2023-11-06T12:12:07+00:00 9da397e5d48d42103ffa60b99caec7a7bef13c8f commit 55702ec9603ebeffb15e6f7b113623fe1d8872f4 upstream. rcutree_report_cpu_starting() must be called before clockevents_register_device() to avoid the following lockdep splat triggered by calling list_add() when CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage ... ----------------------------- kernel/locking/lockdep.c:3680 RCU-list traversed in non-reader section!! other info that might help us debug this: RCU used illegally from offline CPU! rcu_scheduler_active = 1, debug_locks = 1 no locks held by swapper/1/0. ... Call Trace: [<ffffffff8012a434>] show_stack+0x64/0x158 [<ffffffff80a93d98>] dump_stack_lvl+0x90/0xc4 [<ffffffff801c9e9c>] __lock_acquire+0x1404/0x2940 [<ffffffff801cbf3c>] lock_acquire+0x14c/0x448 [<ffffffff80aa4260>] _raw_spin_lock_irqsave+0x50/0x88 [<ffffffff8021e0c8>] clockevents_register_device+0x60/0x1e8 [<ffffffff80130ff0>] r4k_clockevent_init+0x220/0x3a0 [<ffffffff801339d0>] start_secondary+0x50/0x3b8 raw_smp_processor_id() is required in order to avoid calling into lockdep before RCU has declared the CPU to be watched for readers. See also commit 29368e093921 ("x86/smpboot: Move rcu_cpu_starting() earlier"), commit de5d9dae150c ("s390/smp: move rcu_cpu_starting() earlier") and commit 99f070b62322 ("powerpc/smp: Call rcu_cpu_starting() earlier"). Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com> Reviewed-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 55702ec9603ebeffb15e6f7b113623fe1d8872f4 upstream.

rcutree_report_cpu_starting() must be called before
clockevents_register_device() to avoid the following lockdep splat triggered by
calling list_add() when CONFIG_PROVE_RCU_LIST=y:

  WARNING: suspicious RCU usage
  ...
  -----------------------------
  kernel/locking/lockdep.c:3680 RCU-list traversed in non-reader section!!

  other info that might help us debug this:

  RCU used illegally from offline CPU!
  rcu_scheduler_active = 1, debug_locks = 1
  no locks held by swapper/1/0.
  ...
  Call Trace:
  [<ffffffff8012a434>] show_stack+0x64/0x158
  [<ffffffff80a93d98>] dump_stack_lvl+0x90/0xc4
  [<ffffffff801c9e9c>] __lock_acquire+0x1404/0x2940
  [<ffffffff801cbf3c>] lock_acquire+0x14c/0x448
  [<ffffffff80aa4260>] _raw_spin_lock_irqsave+0x50/0x88
  [<ffffffff8021e0c8>] clockevents_register_device+0x60/0x1e8
  [<ffffffff80130ff0>] r4k_clockevent_init+0x220/0x3a0
  [<ffffffff801339d0>] start_secondary+0x50/0x3b8

raw_smp_processor_id() is required in order to avoid calling into lockdep
before RCU has declared the CPU to be watched for readers.

See also commit 29368e093921 ("x86/smpboot:  Move rcu_cpu_starting() earlier"),
commit de5d9dae150c ("s390/smp: move rcu_cpu_starting() earlier") and commit
99f070b62322 ("powerpc/smp: Call rcu_cpu_starting() earlier").

Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPS: kernel: Clear FPU states when setting up kernel threads 2023-12-13T17:45:34+00:00 Thomas Bogendoerfer tsbogend@alpha.franken.de 2023-11-30T16:36:01+00:00 6d9cbae4c032451d41c262cbf8b90018af0dbda0 commit a58a173444a68412bb08849bd81c679395f20ca0 upstream. io_uring sets up the io worker kernel thread via a syscall out of an user space prrocess. This process might have used FPU and since copy_thread() didn't clear FPU states for kernel threads a BUG() is triggered for using FPU inside kernel. Move code around to always clear FPU state for user and kernel threads. Cc: stable@vger.kernel.org Reported-by: Aurelien Jarno <aurel32@debian.org> Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1055021 Suggested-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a58a173444a68412bb08849bd81c679395f20ca0 upstream.

io_uring sets up the io worker kernel thread via a syscall out of an
user space prrocess. This process might have used FPU and since
copy_thread() didn't clear FPU states for kernel threads a BUG()
is triggered for using FPU inside kernel. Move code around
to always clear FPU state for user and kernel threads.

Cc: stable@vger.kernel.org
Reported-by: Aurelien Jarno <aurel32@debian.org>
Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1055021
Suggested-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'mips_6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux 2023-09-07T17:35:14+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-09-07T17:35:14+00:00 ac2224a467b499730057525924f6be3f4fdb0da5 Pull MIPS updates from Thomas Bogendoerfer: "Just cleanups and fixes" * tag 'mips_6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: MIPS: TXx9: Do PCI error checks on own line arch/mips/configs/*_defconfig cleanup MIPS: VDSO: Conditionally export __vdso_gettimeofday() Mips: loongson3_defconfig: Enable ast drm driver by default mips: remove <asm/export.h> mips: replace #include <asm/export.h> with #include <linux/export.h> mips: remove unneeded #include <asm/export.h> MIPS: Loongson64: Fix more __iomem attributes MIPS: loongson32: Remove regs-rtc.h MIPS: loongson32: Remove regs-clk.h MIPS: More explicit DT include clean-ups MIPS: Fixup explicit DT include clean-up Revert MIPS: Loongson: Fix build error when make modules_install MIPS: Only fiddle with CHECKFLAGS if `need-compiler' MIPS: Fix CONFIG_CPU_DADDI_WORKAROUNDS `modules_install' regression MIPS: Explicitly include correct DT includes 
Pull MIPS updates from Thomas Bogendoerfer:
 "Just cleanups and fixes"

* tag 'mips_6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: TXx9: Do PCI error checks on own line
  arch/mips/configs/*_defconfig cleanup
  MIPS: VDSO: Conditionally export __vdso_gettimeofday()
  Mips: loongson3_defconfig: Enable ast drm driver by default
  mips: remove <asm/export.h>
  mips: replace #include <asm/export.h> with #include <linux/export.h>
  mips: remove unneeded #include <asm/export.h>
  MIPS: Loongson64: Fix more __iomem attributes
  MIPS: loongson32: Remove regs-rtc.h
  MIPS: loongson32: Remove regs-clk.h
  MIPS: More explicit DT include clean-ups
  MIPS: Fixup explicit DT include clean-up
  Revert MIPS: Loongson: Fix build error when make modules_install
  MIPS: Only fiddle with CHECKFLAGS if `need-compiler'
  MIPS: Fix CONFIG_CPU_DADDI_WORKAROUNDS `modules_install' regression
  MIPS: Explicitly include correct DT includes
Merge tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty 2023-09-01T16:38:00+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-09-01T16:38:00+00:00 8e1e49550dc85694abd04d86a8ee36bc98bd8b9e Pull tty/serial driver updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.6-rc1. Lots of cleanups in here this cycle, and some driver updates. Short summary is: - Jiri's continued work to make the tty code and apis be a bit more sane with regards to modern kernel coding style and types - cpm_uart driver updates - n_gsm updates and fixes - meson driver updates - sc16is7xx driver updates - 8250 driver updates for different hardware types - qcom-geni driver fixes - tegra serial driver change - stm32 driver updates - synclink_gt driver cleanups - tty structure size reduction All of these have been in linux-next this week with no reported issues. The last bit of cleanups from Jiri and the tty structure size reduction came in last week, a bit late but as they were just style changes and size reductions, I figured they should get into this merge cycle so that others can work on top of them with no merge conflicts" * tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits) tty: shrink the size of struct tty_struct by 40 bytes tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw() tty: n_tty: extract ECHO_OP processing to a separate function tty: n_tty: unify counts to size_t tty: n_tty: use u8 for chars and flags tty: n_tty: simplify chars_in_buffer() tty: n_tty: remove unsigned char casts from character constants tty: n_tty: move newline handling to a separate function tty: n_tty: move canon handling to a separate function tty: n_tty: use MASK() for masking out size bits tty: n_tty: make n_tty_data::num_overrun unsigned tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun() tty: n_tty: use 'num' for writes' counts tty: n_tty: use output character directly tty: n_tty: make flow of n_tty_receive_buf_common() a bool Revert "tty: serial: meson: Add a earlycon for the T7 SoC" Documentation: devices.txt: Fix minors for ttyCPM* Documentation: devices.txt: Remove ttySIOC* Documentation: devices.txt: Remove ttyIOC* serial: 8250_bcm7271: improve bcm7271 8250 port ... 
Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver changes for 6.6-rc1.

  Lots of cleanups in here this cycle, and some driver updates. Short
  summary is:

   - Jiri's continued work to make the tty code and apis be a bit more
     sane with regards to modern kernel coding style and types

   - cpm_uart driver updates

   - n_gsm updates and fixes

   - meson driver updates

   - sc16is7xx driver updates

   - 8250 driver updates for different hardware types

   - qcom-geni driver fixes

   - tegra serial driver change

   - stm32 driver updates

   - synclink_gt driver cleanups

   - tty structure size reduction

  All of these have been in linux-next this week with no reported
  issues. The last bit of cleanups from Jiri and the tty structure size
  reduction came in last week, a bit late but as they were just style
  changes and size reductions, I figured they should get into this merge
  cycle so that others can work on top of them with no merge conflicts"

* tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits)
  tty: shrink the size of struct tty_struct by 40 bytes
  tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw()
  tty: n_tty: extract ECHO_OP processing to a separate function
  tty: n_tty: unify counts to size_t
  tty: n_tty: use u8 for chars and flags
  tty: n_tty: simplify chars_in_buffer()
  tty: n_tty: remove unsigned char casts from character constants
  tty: n_tty: move newline handling to a separate function
  tty: n_tty: move canon handling to a separate function
  tty: n_tty: use MASK() for masking out size bits
  tty: n_tty: make n_tty_data::num_overrun unsigned
  tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
  tty: n_tty: use 'num' for writes' counts
  tty: n_tty: use output character directly
  tty: n_tty: make flow of n_tty_receive_buf_common() a bool
  Revert "tty: serial: meson: Add a earlycon for the T7 SoC"
  Documentation: devices.txt: Fix minors for ttyCPM*
  Documentation: devices.txt: Remove ttySIOC*
  Documentation: devices.txt: Remove ttyIOC*
  serial: 8250_bcm7271: improve bcm7271 8250 port
  ...
Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 2023-08-29T21:53:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-08-29T21:53:51+00:00 d68b4b6f307d155475cce541f2aee938032ed22e Pull non-MM updates from Andrew Morton: - An extensive rework of kexec and crash Kconfig from Eric DeVolder ("refactor Kconfig to consolidate KEXEC and CRASH options") - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a couple of macros to args.h") - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper commands") - vsprintf inclusion rationalization from Andy Shevchenko ("lib/vsprintf: Rework header inclusions") - Switch the handling of kdump from a udev scheme to in-kernel handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory hot un/plug") - Many singleton patches to various parts of the tree * tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits) document while_each_thread(), change first_tid() to use for_each_thread() drivers/char/mem.c: shrink character device's devlist[] array x86/crash: optimize CPU changes crash: change crash_prepare_elf64_headers() to for_each_possible_cpu() crash: hotplug support for kexec_load() x86/crash: add x86 crash hotplug support crash: memory and CPU hotplug sysfs attributes kexec: exclude elfcorehdr from the segment digest crash: add generic infrastructure for crash hotplug support crash: move a few code bits to setup support of crash hotplug kstrtox: consistently use _tolower() kill do_each_thread() nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse scripts/bloat-o-meter: count weak symbol sizes treewide: drop CONFIG_EMBEDDED lockdep: fix static memory detection even more lib/vsprintf: declare no_hash_pointers in sprintf.h lib/vsprintf: split out sprintf() and friends kernel/fork: stop playing lockless games for exe_file replacement adfs: delete unused "union adfs_dirtail" definition ... 
Pull non-MM updates from Andrew Morton:

 - An extensive rework of kexec and crash Kconfig from Eric DeVolder
   ("refactor Kconfig to consolidate KEXEC and CRASH options")

 - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a
   couple of macros to args.h")

 - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper
   commands")

 - vsprintf inclusion rationalization from Andy Shevchenko
   ("lib/vsprintf: Rework header inclusions")

 - Switch the handling of kdump from a udev scheme to in-kernel
   handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory
   hot un/plug")

 - Many singleton patches to various parts of the tree

* tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits)
  document while_each_thread(), change first_tid() to use for_each_thread()
  drivers/char/mem.c: shrink character device's devlist[] array
  x86/crash: optimize CPU changes
  crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()
  crash: hotplug support for kexec_load()
  x86/crash: add x86 crash hotplug support
  crash: memory and CPU hotplug sysfs attributes
  kexec: exclude elfcorehdr from the segment digest
  crash: add generic infrastructure for crash hotplug support
  crash: move a few code bits to setup support of crash hotplug
  kstrtox: consistently use _tolower()
  kill do_each_thread()
  nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse
  scripts/bloat-o-meter: count weak symbol sizes
  treewide: drop CONFIG_EMBEDDED
  lockdep: fix static memory detection even more
  lib/vsprintf: declare no_hash_pointers in sprintf.h
  lib/vsprintf: split out sprintf() and friends
  kernel/fork: stop playing lockless games for exe_file replacement
  adfs: delete unused "union adfs_dirtail" definition
  ...
nmi_backtrace: allow excluding an arbitrary CPU 2023-08-18T17:19:00+00:00 Douglas Anderson dianders@chromium.org 2023-08-04T14:00:42+00:00 8d539b84f1e3478436f978ceaf55a0b6cab497b5 The APIs that allow backtracing across CPUs have always had a way to exclude the current CPU. This convenience means callers didn't need to find a place to allocate a CPU mask just to handle the common case. Let's extend the API to take a CPU ID to exclude instead of just a boolean. This isn't any more complex for the API to handle and allows the hardlockup detector to exclude a different CPU (the one it already did a trace for) without needing to find space for a CPU mask. Arguably, this new API also encourages safer behavior. Specifically if the caller wants to avoid tracing the current CPU (maybe because they already traced the current CPU) this makes it more obvious to the caller that they need to make sure that the current CPU ID can't change. [akpm@linux-foundation.org: fix trigger_allbutcpu_cpu_backtrace() stub] Link: https://lkml.kernel.org/r/20230804065935.v4.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: kernel test robot <lkp@intel.com> Cc: Lecopzer Chen <lecopzer.chen@mediatek.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 
The APIs that allow backtracing across CPUs have always had a way to
exclude the current CPU.  This convenience means callers didn't need to
find a place to allocate a CPU mask just to handle the common case.

Let's extend the API to take a CPU ID to exclude instead of just a
boolean.  This isn't any more complex for the API to handle and allows the
hardlockup detector to exclude a different CPU (the one it already did a
trace for) without needing to find space for a CPU mask.

Arguably, this new API also encourages safer behavior.  Specifically if
the caller wants to avoid tracing the current CPU (maybe because they
already traced the current CPU) this makes it more obvious to the caller
that they need to make sure that the current CPU ID can't change.

[akpm@linux-foundation.org: fix trigger_allbutcpu_cpu_backtrace() stub]
Link: https://lkml.kernel.org/r/20230804065935.v4.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>