korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-11 12:28:41 +08:00
Code Issues Packages Projects Releases Wiki Activity

A single scheduler fix to ensure that there is no stale KASAN shadow state

Browse Source 
left on the idle task's stack when a CPU is brought up after it was brought
 down before.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmGjr0UTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoadaD/0Q3hMjI+N3AigZiBToGccafOfsmiMH
 fJ6fUM7gh4pTrGuoDQSGt02zYNYx9Zx7X8PpiuWAAIKbppiKmvniCgPMgMGARUBn
 UQ/W2XWUiu/wtleRf4JtE6VwHciNVgLdnWIazRWsjDryUXVcJwhn8J1o5K6LnwjD
 Rof/aYuVR47DprYG03OI0FD1GwlSPWMbAgB6OlJS6ZRvpq+7ergVKA0PQAY7ZZko
 vBlDU7Sq4dJ2CE4aiRGLyLNhZfrubmfeMP2UVmVSpMBta7zs+YmaYjZvKfgO3KZT
 OVbyFfDbL8FJgUmTSI1WBKq+W44o1D1e8VrKiCFj+y5w9diHW9OQEg2wqQdsMB6a
 QgNgDZjg8UHancF5O2kNYjnUVGgxUww7PftWbxkg4VAUmlCzhbZAAegspZHow0mU
 zcqDaMTky0FbcbB/Ukik/HG6J3KrR34GYjui3fe0wZHZlDim6azZucRTd+x9jRsB
 jPUlE3DW0JfNFKcMnlLLNvS8h3j7iCbb3XDv1y4BW0+EB76IsCThjqFO0dIPpiju
 T9ituTr6p4+B4U37Cz5qOMgUSha+f9/6blYG8NgCeHyD2l5HDnavO9lGhoP3jsZJ
 LJRa8mWd+oZbZlpBtTkaSOA55cTxonsIuCseTdXlfsVtzuJBmLKwdRPuDSRCEo0G
 xH1vNNUba86+6A==
 =ne0K
 -----END PGP SIGNATURE-----

Merge tag 'sched-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fix from Thomas Gleixner:
 "A single scheduler fix to ensure that there is no stale KASAN shadow
  state left on the idle task's stack when a CPU is brought up after it
  was brought down before"

* tag 'sched-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/scs: Reset task stack state in bringup_cpu()
This commit is contained in:
Linus Torvalds 2021-11-28 09:15:34 -08:00
commit 97891bbf38
2 changed files with 7 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
kernel/cpu.c
View File

@ -31,6 +31,7 @@
#include <linux/smpboot.h>
#include <linux/relay.h>
#include <linux/slab.h>
#include <linux/scs.h>
#include <linux/percpu-rwsem.h>
#include <linux/cpuset.h>
@ -587,6 +588,12 @@ static int bringup_cpu(unsigned int cpu)
struct task_struct *idle = idle_thread_get(cpu);
int ret;
/*
* Reset stale stack state from the last time this CPU was online.
*/
scs_task_reset(idle);
kasan_unpoison_task_stack(idle);
/*
* Some architectures have to walk the irq descriptors to
* setup the vector space for the cpu which comes online.

4
kernel/sched/core.c
View File

@ -8619,9 +8619,6 @@ void __init init_idle(struct task_struct *idle, int cpu)
idle->flags |= PF_IDLE | PF_KTHREAD | PF_NO_SETAFFINITY;
kthread_set_per_cpu(idle, cpu);
scs_task_reset(idle);
kasan_unpoison_task_stack(idle);
#ifdef CONFIG_SMP
/*
* It's possible that init_idle() gets called multiple times on a task,
@ -8777,7 +8774,6 @@ void idle_task_exit(void)
finish_arch_post_lock_switch();
}
scs_task_reset(current);
/* finish_cpu(), as ran on the BP, will clean up the active_mm state */
}