On Sat, 5 Jan 2013 10:25:38 +0800 Ming Lei <ming.lei@xxxxxxxxxxxxx> wrote: > This patchset try to solve one deadlock problem which might be caused > by memory allocation with block I/O during runtime PM and block device > error handling path. Traditionly, the problem is addressed by passing > GFP_NOIO statically to mm, but that is not a effective solution, see > detailed description in patch 1's commit log. > > This patch set introduces one process flag and trys to fix the deadlock > problem on block device/network device during runtime PM or usb bus reset. The patchset doesn't look like the worst thing I've ever applied ;) One thing I'm wondering: during suspend and resume, why are GFP_KERNEL allocation attempts even getting down to the device layer? Presumably the page scanner is encountering dirty pagecache or dirty swapcache pages? If so, I wonder if we could avoid the whole problem by appropriately syncing all dirty memory back to storage before starting to turn devices off? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>