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[hurd,commited] htl: Fix sem_wait race between read and gsync_wait

Message ID 20221229234210.2931558-1-samuel.thibault@ens-lyon.org
State New
Headers show
Series [hurd,commited] htl: Fix sem_wait race between read and gsync_wait | expand

Commit Message

Samuel Thibault Dec. 29, 2022, 11:42 p.m. UTC 
If the value changes between sem_wait's read and the gsync_wait call,
the kernel will return KERN_INVALID_ARGUMENT, which we have to interpret
as the value having already changed.

This fixes applications (e.g. libgo) seeing sem_wait erroneously return
KERN_INVALID_ARGUMENT.
---
 sysdeps/htl/sem-timedwait.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/sysdeps/htl/sem-timedwait.c b/sysdeps/htl/sem-timedwait.c
index 1b1eec9f59..c610804b08 100644
--- a/sysdeps/htl/sem-timedwait.c
+++ b/sysdeps/htl/sem-timedwait.c
@@ -79,7 +79,7 @@  __sem_timedwait_internal (sem_t *restrict sem,
 		      ((unsigned int *) &sem->data) + SEM_VALUE_OFFSET,
 		      0, flags);
 
-	  if (err != 0)
+	  if (err != 0 && err != KERN_INVALID_ARGUMENT)
 	    {
 	      /* Error, interruption or timeout, abort.  */
 	      if (err == KERN_TIMEDOUT)
@@ -138,7 +138,7 @@  __sem_timedwait_internal (sem_t *restrict sem,
 		err = __lll_wait_intr (&isem->value,
 			  SEM_NWAITERS_MASK, flags);
 
-	      if (err != 0)
+	      if (err != 0 && err != KERN_INVALID_ARGUMENT)
 		{
 		  /* Error, interruption or timeout, abort.  */
 		  if (err == KERN_TIMEDOUT)