From: Neil Brown Date: Tue, 15 Sep 2009 23:05:51 +0000 (-0700) Subject: sysfs: Allow sysfs_notify_dirent to be called from interrupt context. X-Git-Tag: v2.6.32-rc5~10^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=83db93f4de2d9ae441a491d1dc61c2204f0195de;p=pandora-kernel.git sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados Signed-off-by: NeilBrown Signed-off-by: Dan Williams Cc: stable Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed