kernel.git/arch/arc/kernel/troubleshoot.c, branch linux-5.18.y

arch/arc/kernel/troubleshoot: use vma_lookup() instead of find_vma()

2021-06-29T17:53:51Z

Use vma_lookup() to find the VMA at a specific address. As vma_lookup() will return NULL if the address is not within any VMA, the start address no longer needs to be validated. Link: https://lkml.kernel.org/r/20210521174745.2219620-4-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett Reviewed-by: Laurent Dufour Acked-by: David Hildenbrand Acked-by: Davidlohr Bueso Cc: Geert Uytterhoeven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ARC: show_regs: fix r12 printing and simplify

2020-08-27T20:11:37Z

when working on ARC64, spotted an issue in ARCv2 reg file printing. print_reg_file() assumes contiguous reg-file whereas in ARCv2 they are not: r12 comes before r0-r11 due to hardware auto-save. Apparently this issue has been present since v2 port submission. To avoid bolting hacks for this discontinuity while looping through pt_regs, just ditching the loop and print pt_regs directly. Signed-off-by: Vineet Gupta

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

2020-06-09T16:39:14Z

This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse Signed-off-by: Andrew Morton Reviewed-by: Daniel Jordan Reviewed-by: Laurent Dufour Reviewed-by: Vlastimil Babka Cc: Davidlohr Bueso Cc: David Rientjes Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: John Hubbard Cc: Liam Howlett Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Ying Han Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds

arc: add show_stack_loglvl()

2020-06-09T16:39:10Z

Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). As a good side-effect header "Stack Trace:" is now printed with the same log level as the rest of backtrace. [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov Signed-off-by: Andrew Morton Cc: Vineet Gupta Link: http://lkml.kernel.org/r/20200418201944.482088-4-dima@arista.com Signed-off-by: Linus Torvalds

ARC: show_regs: avoid extra line of output

2020-05-14T22:05:00Z

Signed-off-by: Vineet Gupta

ARC: show_regs: reduce lines of output

2020-03-11T17:07:13Z

Before ------ | CPU: 1 PID: 29061 Comm: tst-dynarray-at Not tainted 5.6.0-rc1-00002-g941fcc018ca6-dirty #12 | | [ECR ]: 0x00090000 => | [EFA ]: 0x00000000 | [ERET ]: 0x2004aa6c | @off 0x2aa6c in [/lib/libc-2.31.9000.so] VMA: 0x20020000 to 0x20122000 | [STAT32]: 0x80080a82 [IE U ] | BTA: 0x2004aa18 SP: 0x5ffff8a8 FP: 0x5ffff8fc | LPS: 0x2008788e LPE: 0x20087896 LPC: 0x00000000 | r00: 0x00000000 r01: 0x5ffff8a8 r02: 0x00000000 | r03: 0x00000008 r04: 0xffffffff r05: 0x00000000 | r06: 0x00000000 r07: 0x00000000 r08: 0x00000087 | r09: 0x00000000 r10: 0x2010691c r11: 0x00000020 | r12: 0x2003b214 r13: 0x5ffff8a8 r14: 0x20126e68 | r15: 0x2001f26c r16: 0x2012a000 r17: 0x00000001 | r18: 0x5ffff8fc r19: 0x00000000 r20: 0x5ffff948 | r21: 0x00000001 r22: 0xffffffff r23: 0x5fffff8c | r24: 0x4008c2a8 r25: 0x2001f6e0 After ----- | CPU: 1 PID: 29061 Comm: tst-dynarray-at Not tainted 5.6.0-rc1-00002-g941fcc018ca6-dirty #12 | @off 0x2aa6c in [/lib/libc-2.31.9000.so] VMA: 0x20020000 to 0x20122000 | ECR: 0x00090000 EFA: 0x00000000 ERET: 0x2004aa6c | STAT32: 0x80080a82 [IE U ] BTA: 0x2004aa18 | BLK: 0x2003b214 SP: 0x5ffff8a8 FP: 0x5ffff8fc | LPS: 0x2008788e LPE: 0x20087896 LPC: 0x00000000 | r00: 0x00000000 r01: 0x5ffff8a8 r02: 0x00000000 | r03: 0x00000008 r04: 0xffffffff r05: 0x00000000 | r06: 0x00000000 r07: 0x00000000 r08: 0x00000087 | r09: 0x00000000 r10: 0x2010691c r11: 0x00000020 | r12: 0x2003b214 r13: 0x5ffff8a8 r14: 0x20126e68 | r15: 0x2001f26c r16: 0x2012a000 r17: 0x00000001 | r18: 0x5ffff8fc r19: 0x00000000 r20: 0x5ffff948 | r21: 0x00000001 r22: 0xffffffff r23: 0x5fffff8c | r24: 0x4008c2a8 r25: 0x2001f6e0 BTA: 0x2004aa18 Signed-off-by: Vineet Gupta

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 332

2019-06-05T15:37:06Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as publishhed by the free software foundation extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 48 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Alexios Zavras Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.292339952@linutronix.de Signed-off-by: Greg Kroah-Hartman

ARCv2: Add explcit unaligned access support (and ability to disable too)

2019-02-25T20:10:58Z

As of today we enable unaligned access unconditionally on ARCv2. Do this under a Kconfig option to allow disable it for test, benchmarking etc. Also while at it - Select HAVE_EFFICIENT_UNALIGNED_ACCESS - Although gcc defaults to unaligned access (since GNU 2018.03), add the right toggles for enabling or disabling as appropriate - update bootlog to prints both HW feature status (exists, enabled/disabled) and SW status (used / not used). - wire up the relaxed memcpy for unaligned access Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta [vgupta: squashed patches, handle gcc -mno-unaligned-access quick]

ARC: show_regs: lockdep: re-enable preemption

2019-01-17T22:38:00Z

signal handling core calls show_regs() with preemption disabled which on ARC takes mmap_sem for mm/vma access, causing lockdep splat. | [ARCLinux]# ./segv-null-ptr | potentially unexpected fatal signal 11. | BUG: sleeping function called from invalid context at kernel/fork.c:1011 | in_atomic(): 1, irqs_disabled(): 0, pid: 70, name: segv-null-ptr | no locks held by segv-null-ptr/70. | CPU: 0 PID: 70 Comm: segv-null-ptr Not tainted 4.18.0+ #69 | | Stack Trace: | arc_unwind_core+0xcc/0x100 | ___might_sleep+0x17a/0x190 | mmput+0x16/0xb8 | show_regs+0x52/0x310 | get_signal+0x5ee/0x610 | do_signal+0x2c/0x218 | resume_user_mode_begin+0x90/0xd8 Workaround by re-enabling preemption temporarily. Note that the preemption disabling in core code around show_regs() was introduced by commit 3a9f84d354ce ("signals, debug: fix BUG: using smp_processor_id() in preemptible code in print_fatal_signal()") to silence a differnt lockdep seen on x86 bakc in 2009. Cc: Signed-off-by: Vineet Gupta

ARC: show_regs: lockdep: avoid page allocator...

2019-01-17T22:38:00Z

and use smaller/on-stack buffer instead The motivation for this change was lockdep splat like below. | potentially unexpected fatal signal 11. | BUG: sleeping function called from invalid context at ../mm/page_alloc.c:4317 | in_atomic(): 1, irqs_disabled(): 0, pid: 57, name: segv | no locks held by segv/57. | Preemption disabled at: | [<8182f17e>] get_signal+0x4a6/0x7c4 | CPU: 0 PID: 57 Comm: segv Not tainted 4.17.0+ #23 | | Stack Trace: | arc_unwind_core.constprop.1+0xd0/0xf4 | __might_sleep+0x1f6/0x234 | __get_free_pages+0x174/0xca0 | show_regs+0x22/0x330 | get_signal+0x4ac/0x7c4 # print_fatal_signals() -> preempt_disable() | do_signal+0x30/0x224 | resume_user_mode_begin+0x90/0xd8 So signal handling core calls show_regs() with preemption disabled but an ensuing GFP_KERNEL page allocator call is flagged by lockdep. We could have switched to GFP_NOWAIT, but turns out that is not enough anways and eliding page allocator call leads to less code and instruction traces to sift thru when debugging pesky crashes. FWIW, this patch doesn't cure the lockdep splat (which next patch does). Reviewed-by: William Kucharski Signed-off-by: Vineet Gupta