Patch "dm ioctl: set noio flag to avoid __vmalloc deadlock" has been added to the 3.10-stable tree

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This is a note to let you know that I've just added the patch titled

    dm ioctl: set noio flag to avoid __vmalloc deadlock

to the 3.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dm-ioctl-set-noio-flag-to-avoid-__vmalloc-deadlock.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 1c0e883e86ece31880fac2f84b260545d66a39e0 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Wed, 10 Jul 2013 23:41:15 +0100
Subject: dm ioctl: set noio flag to avoid __vmalloc deadlock

From: Mikulas Patocka <mpatocka@xxxxxxxxxx>

commit 1c0e883e86ece31880fac2f84b260545d66a39e0 upstream.

Set noio flag while calling __vmalloc() because it doesn't fully respect
gfp flags to avoid a possible deadlock (see commit
502624bdad3dba45dfaacaf36b7d83e39e74b2d2).

This should be backported to stable kernels 3.8 and newer. The kernel 3.8
doesn't have memalloc_noio_save(), so we should set and restore process
flag PF_MEMALLOC instead.

Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Alasdair G Kergon <agk@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/md/dm-ioctl.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1644,7 +1644,10 @@ static int copy_params(struct dm_ioctl _
 	}
 
 	if (!dmi) {
+		unsigned noio_flag;
+		noio_flag = memalloc_noio_save();
 		dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_REPEAT | __GFP_HIGH, PAGE_KERNEL);
+		memalloc_noio_restore(noio_flag);
 		if (dmi)
 			*param_flags |= DM_PARAMS_VMALLOC;
 	}


Patches currently in stable-queue which might be from mpatocka@xxxxxxxxxx are

queue-3.10/dm-verity-fix-inability-to-use-a-few-specific-devices-sizes.patch
queue-3.10/dm-ioctl-set-noio-flag-to-avoid-__vmalloc-deadlock.patch
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