call_usermodehelper(): increase reliability
authorKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Fri, 25 Jul 2008 08:45:38 +0000 (01:45 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 25 Jul 2008 17:53:28 +0000 (10:53 -0700)
commitac331d158e198d2a91a5b0a3ec4ca9991fdb57af
treeb0921e2bc8e59d5df2c554c41c3b9f04e05d6d7c
parentf557d0996a6f9c06912528ea85e1dba0fb7d485f
call_usermodehelper(): increase reliability

Presently call_usermodehelper_setup() uses GFP_ATOMIC.  but it can return
NULL _very_ easily.

GFP_ATOMIC is needed only when we can't sleep.  and, GFP_KERNEL is robust
and better.

thus, I add gfp_mask argument to call_usermodehelper_setup().

So, its callers pass the gfp_t as below:

call_usermodehelper() and call_usermodehelper_keys():
depend on 'wait' argument.
call_usermodehelper_pipe():
always GFP_KERNEL because always run under process context.
orderly_poweroff():
pass to GFP_ATOMIC because may run under interrupt context.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: "Paul Menage" <menage@google.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/kmod.h
kernel/kmod.c
kernel/sys.c