[lkml]   [2003]   [Mar]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [CHECKER] potential races in kernel/*.c mm/*.c net/*ipv4*.c
On Tue, 4 Mar 2003, Dawson Engler wrote:
> BUG? pair: lock=<struct shmem_inode_info.lock>, var=<struct shmem_inode_info.next_index>
> z score=0.20
> first = 2
> 1 error out of 6 uses:
> /u2/engler/mc/oses/linux/linux-2.5.62/mm/shmem.c:385:shmem_truncate: ERROR: var <struct shmem_inode_info.next_index> not protected by <struct shmem_inode_info.lock>(pop=6, s=5) [locked=0] [seen_lock=1]
> seems like a potential race, since info_next_index seems like it could
> get decreased in the meantime violating the if-stmt:
> if (idx >= info->next_index)
> return;
> spin_lock(&info->lock);
> limit = info->next_index;

Thanks for the report, but this one is okay as is.

info->next_index is only ever _decreased_ here in this shmem_truncate
function, which is always entered under the protection of inode->i_sem
(which is guarding corresponding changes to inode->i_size). As you've
noticed, it's okay if next_index increases before spin lock is taken.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:33    [W:0.172 / U:0.472 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site