| Message ID | 1344520529-19164-1-git-send-email-makienko@ispras.ru |
|---|---|
| State | Rejected |
| Delegated to: | David Miller |
| Headers | show |
On Thu, 9 Aug 2012 17:55:20 +0400 Marina Makienko <makienko@ispras.ru> wrote: > The function blk_get_request() can return NULL in some cases. There are > checks on it if function is called with argumetns one of which is > GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request > blk_get_request() return NULL. drivers/ide is obsolete and scheduled for removal. I'm not sure messing with it is remotely useful at this point ? -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Alan Cox <alan@lxorguk.ukuu.org.uk> Date: Thu, 9 Aug 2012 15:13:42 +0100 > On Thu, 9 Aug 2012 17:55:20 +0400 > Marina Makienko <makienko@ispras.ru> wrote: > >> The function blk_get_request() can return NULL in some cases. There are >> checks on it if function is called with argumetns one of which is >> GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request >> blk_get_request() return NULL. > > drivers/ide is obsolete and scheduled for removal. I'm not sure messing > with it is remotely useful at this point ? Agreed, I'm not applying this stuff. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hello. On 09.08.2012 18:13, Alan Cox wrote: > On Thu, 9 Aug 2012 17:55:20 +0400 > Marina Makienko <makienko@ispras.ru> wrote: >> The function blk_get_request() can return NULL in some cases. There are >> checks on it if function is called with argumetns one of which is >> GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request >> blk_get_request() return NULL. > drivers/ide is obsolete and scheduled for removal. When it was scheduled for removal? I can't find an entry in Documentation/feature-removal-schedule.txt. And how can that be when there are still many unconverted drivers? > I'm not sure messing with it is remotely useful at this point ? It's being maintained for bug fixes still, AFAIK. MBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index fac3d9d..8bf4109 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -93,6 +93,12 @@ int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk, int error; rq = blk_get_request(drive->queue, READ, __GFP_WAIT); + + if (!rq) { + printk(KERN_ERR PFX"ide_queue_pc_tail: blk_get_request() failed. \n"); + return 1; + } + rq->cmd_type = REQ_TYPE_SPECIAL; rq->special = (char *)pc;
The function blk_get_request() can return NULL in some cases. There are checks on it if function is called with argumetns one of which is GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request blk_get_request() return NULL. But if there is function call with argument __GFP_WAIT the system will wait until get request or the queue becomes dead. If something kills the queue, blk_get_request() return NULL and next operations will lead to errors. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Marina Makienko <makienko@ispras.ru> --- drivers/ide/ide-atapi.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)