linux-stable.git/kernel/reboot.c, branch v5.4.285

kernel/reboot: emergency_restart: Set correct system_state

2023-11-28T16:50:19+00:00

commit 60466c067927abbcaff299845abd4b7069963139 upstream.

As the emergency restart does not call kernel_restart_prepare(), the
system_state stays in SYSTEM_RUNNING.

Since bae1d3a05a8b, this hinders i2c_in_atomic_xfer_mode() from becoming
active, and therefore might lead to avoidable warnings in the restart
handlers, e.g.:

[   12.667612] WARNING: CPU: 1 PID: 1 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x33c/0x6b0
[   12.676926] Voluntary context switch within RCU read-side critical section!
...
[   12.742376]  schedule_timeout from wait_for_completion_timeout+0x90/0x114
[   12.749179]  wait_for_completion_timeout from tegra_i2c_wait_completion+0x40/0x70
...
[   12.994527]  atomic_notifier_call_chain from machine_restart+0x34/0x58
[   13.001050]  machine_restart from panic+0x2a8/0x32c

Avoid these by setting the correct system_state.

Fixes: bae1d3a05a8b ("i2c: core: remove use of in_atomic()")
Cc: stable@vger.kernel.org # v5.2+
Reviewed-by: Dmitry Osipenko 
Tested-by: Nishanth Menon 
Signed-off-by: Benjamin Bara 
Link: https://lore.kernel.org/r/20230327-tegra-pmic-reboot-v7-1-18699d5dcd76@skidata.com
Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman

reboot: fix overflow parsing reboot cpu number

2020-11-18T18:20:30+00:00

commit df5b0ab3e08a156701b537809914b339b0daa526 upstream.

Limit the CPU number to num_possible_cpus(), because setting it to a
value lower than INT_MAX but higher than NR_CPUS produces the following
error on reboot and shutdown:

    BUG: unable to handle page fault for address: ffffffff90ab1bb0
    #PF: supervisor read access in kernel mode
    #PF: error_code(0x0000) - not-present page
    PGD 1c09067 P4D 1c09067 PUD 1c0a063 PMD 0
    Oops: 0000 [#1] SMP
    CPU: 1 PID: 1 Comm: systemd-shutdow Not tainted 5.9.0-rc8-kvm #110
    Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
    RIP: 0010:migrate_to_reboot_cpu+0xe/0x60
    Code: ea ea 00 48 89 fa 48 c7 c7 30 57 f1 81 e9 fa ef ff ff 66 2e 0f 1f 84 00 00 00 00 00 53 8b 1d d5 ea ea 00 e8 14 33 fe ff 89 da <48> 0f a3 15 ea fc bd 00 48 89 d0 73 29 89 c2 c1 e8 06 65 48 8b 3c
    RSP: 0018:ffffc90000013e08 EFLAGS: 00010246
    RAX: ffff88801f0a0000 RBX: 0000000077359400 RCX: 0000000000000000
    RDX: 0000000077359400 RSI: 0000000000000002 RDI: ffffffff81c199e0
    RBP: ffffffff81c1e3c0 R08: ffff88801f41f000 R09: ffffffff81c1e348
    R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
    R13: 00007f32bedf8830 R14: 00000000fee1dead R15: 0000000000000000
    FS:  00007f32bedf8980(0000) GS:ffff88801f480000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffffffff90ab1bb0 CR3: 000000001d057000 CR4: 00000000000006a0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
      __do_sys_reboot.cold+0x34/0x5b
      do_syscall_64+0x2d/0x40

Fixes: 1b3a5d02ee07 ("reboot: move arch/x86 reboot= handling to generic kernel")
Signed-off-by: Matteo Croce 
Signed-off-by: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Fabian Frederick 
Cc: Greg Kroah-Hartman 
Cc: Guenter Roeck 
Cc: Kees Cook 
Cc: Mike Rapoport 
Cc: Pavel Tatashin 
Cc: Petr Mladek 
Cc: Robin Holt 
Cc: 
Link: https://lkml.kernel.org/r/20201103214025.116799-3-mcroce@linux.microsoft.com
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

Revert "kernel/reboot.c: convert simple_strtoul to kstrtoint"

2020-11-18T18:20:30+00:00

commit 8b92c4ff4423aa9900cf838d3294fcade4dbda35 upstream.

Patch series "fix parsing of reboot= cmdline", v3.

The parsing of the reboot= cmdline has two major errors:

 - a missing bound check can crash the system on reboot

 - parsing of the cpu number only works if specified last

Fix both.

This patch (of 2):

This reverts commit 616feab753972b97.

kstrtoint() and simple_strtoul() have a subtle difference which makes
them non interchangeable: if a non digit character is found amid the
parsing, the former will return an error, while the latter will just
stop parsing, e.g.  simple_strtoul("123xyx") = 123.

The kernel cmdline reboot= argument allows to specify the CPU used for
rebooting, with the syntax `s####` among the other flags, e.g.
"reboot=warm,s31,force", so if this flag is not the last given, it's
silently ignored as well as the subsequent ones.

Fixes: 616feab75397 ("kernel/reboot.c: convert simple_strtoul to kstrtoint")
Signed-off-by: Matteo Croce 
Signed-off-by: Andrew Morton 
Cc: Guenter Roeck 
Cc: Petr Mladek 
Cc: Arnd Bergmann 
Cc: Mike Rapoport 
Cc: Kees Cook 
Cc: Pavel Tatashin 
Cc: Robin Holt 
Cc: Fabian Frederick 
Cc: Greg Kroah-Hartman 
Cc: 
Link: https://lkml.kernel.org/r/20201103214025.116799-2-mcroce@linux.microsoft.com
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

panic/reboot: allow specifying reboot_mode for panic only

2019-05-15T02:52:51+00:00

Allow specifying reboot_mode for panic only.  This is needed on systems
where ramoops is used to store panic logs, and user wants to use warm
reset to preserve those, while still having cold reset on normal
reboots.

Link: http://lkml.kernel.org/r/20190322004735.27702-1-aaro.koskinen@iki.fi
Signed-off-by: Aaro Koskinen 
Reviewed-by: Kees Cook 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/reboot.c: export pm_power_off_prepare

2018-09-11T15:13:24+00:00

Export pm_power_off_prepare. It is needed to implement power off on
Freescale/NXP iMX6 based boards with external power management
integrated circuit (PMIC).

Signed-off-by: Oleksij Rempel 
Signed-off-by: Mark Brown

PM / reboot: Eliminate race between reboot and suspend

2018-08-06T10:35:20+00:00

At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.

Signed-off-by: Pingfan Liu 
Acked-by: Pavel Machek 
Signed-off-by: Rafael J. Wysocki

kernel/reboot.c: add devm_register_reboot_notifier()

2017-11-18T00:10:04+00:00

Add devm_* wrapper around register_reboot_notifier to simplify device
specific reboot notifier registration/unregistration.

[akpm@linux-foundation.org: move `struct device' forward decl to top-of-file]
Link: http://lkml.kernel.org/r/20170320171753.1705-1-andrew.smirnov@gmail.com
Signed-off-by: Andrey Smirnov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: split kexec_load syscall from kexec core code

2015-09-10T20:29:01+00:00

There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young 
Cc: Eric W. Biederman 
Cc: Vivek Goyal 
Cc: Petr Tesarik 
Cc: Theodore Ts'o 
Cc: Josh Boyer 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/reboot.c: add orderly_reboot for graceful reboot

2015-04-15T23:35:23+00:00

The kernel has orderly_poweroff which allows the kernel to initiate a
graceful shutdown of userspace, by running /sbin/poweroff.  This adds
orderly_reboot that will cause userspace to shut itself down by calling
/sbin/reboot.

This will be used for shutdown initiated by a system controller on
platforms that do not use ACPI.

orderly_reboot() should be used when the system wants to allow userspace
to gracefully shut itself down.  For cases where the system may imminently
catch on fire, the existing emergency_restart() provides an immediate
reboot without involving userspace.

Signed-off-by: Joel Stanley 
Cc: Fabian Frederick 
Cc: Benjamin Herrenschmidt 
Cc: Michael Ellerman 
Cc: Rusty Russell 
Cc: Jeremy Kerr 
Cc: David S. Miller 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds