dlan17/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge tag 'core-rseq-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Browse Source 
Pull rseq updates from Thomas Gleixner:
 "Two fixes for RSEQ:

   - Protect the event mask modification against the membarrier() IPI as
     otherwise the RmW operation is unprotected and events might be lost

   - Fix the weak symbol reference in rseq selftests

     The current weak RSEQ symbols definitions which were added to allow
     static linkage are not working correctly as they effectively
     re-define the glibc symbols leading to multiple versions of the
     symbols when compiled with -fno-common.

     Mark them as 'extern' to convert them from weak symbol definitions
     to weak symbol references. That works with static and dynamic
     linkage independent of -fcommon and -fno-common"

* tag 'core-rseq-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq/selftests: Use weak symbol reference, not definition, to link with glibc
  rseq: Protect event mask against membarrier IPI
This commit is contained in:
Linus Torvalds
2025-09-30 15:06:33 -07:00
parent 7601d18be0 a001cd248a
commit 1d17e808cf
3 changed files with 17 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel/rseq.c
+5 -5
View File
@@ -342,12 +342,12 @@ static int rseq_need_restart(struct task_struct *t, u32 cs_flags)
/*
* Load and clear event mask atomically with respect to
* scheduler preemption.
* scheduler preemption and membarrier IPIs.
*/
preempt_disable();
event_mask = t->rseq_event_mask;
t->rseq_event_mask = 0;
preempt_enable();
scoped_guard(RSEQ_EVENT_GUARD) {
event_mask = t->rseq_event_mask;
t->rseq_event_mask = 0;
}
return !!event_mask;
}