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| author | Oleg Nesterov <oleg@tv-sign.ru> | 2008-06-08 21:20:43 +0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-10-14 17:15:33 +0200 |
| commit | 85462323555dda749f1c5373a8d72679464c968d (patch) | |
| tree | aeec1f9a2ad6665c70a88483cbe5e9a3a2f33536 /mm | |
| parent | 7591103c08abade60aeddb432ed0686ddd0de1c6 (diff) | |
| download | linux-85462323555dda749f1c5373a8d72679464c968d.tar.gz linux-85462323555dda749f1c5373a8d72679464c968d.tar.bz2 linux-85462323555dda749f1c5373a8d72679464c968d.zip | |
do_generic_file_read: s/EINTR/EIO/ if lock_page_killable() fails
If lock_page_killable() fails because the task was killed by SIGKILL or
any other fatal signal, do_generic_file_read() returns -EIO.
This seems to be OK, because in fact the userspace won't see this error,
the task will dequeue SIGKILL and exit.
However, /sbin/init is different, it will dequeue SIGKILL, ignore it, and
return to the user-space with the bogus -EIO.
Change the code to return the error code from lock_page_killable(), -EINTR.
This doesn't fix the bug, but perhaps makes sense anyway. Imho, with this
change the code looks a bit more logical, and the "good" init should handle
the spurious EINTR or short read.
Afaics we can also change lock_page_killable() to return -ERESTARTNOINTR,
but this can't prevent the short reads.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/filemap.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 876bc595d0f8..494ff20b6cfa 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1100,8 +1100,9 @@ page_ok: page_not_up_to_date: /* Get exclusive access to the page ... */ - if (lock_page_killable(page)) - goto readpage_eio; + error = lock_page_killable(page); + if (unlikely(error)) + goto readpage_error; page_not_up_to_date_locked: /* Did it get truncated before we got the lock? */ @@ -1130,8 +1131,9 @@ readpage: } if (!PageUptodate(page)) { - if (lock_page_killable(page)) - goto readpage_eio; + error = lock_page_killable(page); + if (unlikely(error)) + goto readpage_error; if (!PageUptodate(page)) { if (page->mapping == NULL) { /* @@ -1143,15 +1145,14 @@ readpage: } unlock_page(page); shrink_readahead_size_eio(filp, ra); - goto readpage_eio; + error = -EIO; + goto readpage_error; } unlock_page(page); } goto page_ok; -readpage_eio: - error = -EIO; readpage_error: /* UHHUH! A synchronous read error occurred. Report it */ desc->error = error; |