Re: [PATCH v6 0/6] solve deadlock caused by memory allocation withI/O

[Andrew Morton]

On Sat, 24 Nov 2012 20:59:12 +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 1st one is the change on include/sched.h and mm.
> 
> The 2nd patch introduces the flag of memalloc_noio on 'dev_pm_info',
> and pm_runtime_set_memalloc_noio(), so that PM Core can teach mm to not
> allocate mm with GFP_IO during the runtime_resume callback only on
> device with the flag set.
> 
> The following 2 patches apply the introduced pm_runtime_set_memalloc_noio()
> to mark all devices as memalloc_noio_resume in the path from the block or
> network device to the root device in device tree.
> 
> The last 2 patches are applied again PM and USB subsystem to demonstrate
> how to use the introduced mechanism to fix the deadlock problem.
> 
> Andrew, could you queue these patches into your tree since V6 fixes all
> your concerns and looks no one objects these patches?

Yes, this patchset looks ready to run with.  But as we're at -rc7 I'll ask
you to refresh, retest and resend after 3.8-rc1, please.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/