linux-toradex.git/drivers/block, branch v4.9.30

nbd: fix 64-bit division

2017-04-21T07:31:23+00:00

commit e88f72cb9f54f6d244e55f629fe5e2f34ca6f9ed upstream.

We have this:

ERROR: "__aeabi_ldivmod" [drivers/block/nbd.ko] undefined!
ERROR: "__divdi3" [drivers/block/nbd.ko] undefined!
nbd.c:(.text+0x247c72): undefined reference to `__divdi3'

due to a recent commit, that did 64-bit division. Use the proper
divider function so that 32-bit compiles don't break.

Fixes: ef77b515243b ("nbd: use loff_t for blocksize and nbd_set_size args")
Signed-off-by: Jens Axboe 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

nbd: use loff_t for blocksize and nbd_set_size args

2017-04-21T07:31:23+00:00

commit ef77b515243b3499d62cf446eda6ca7e0a0b079c upstream.

If we have large devices (say like the 40t drive I was trying to test with) we
will end up overflowing the int arguments to nbd_set_size and not get the right
size for our device.  Fix this by using loff_t everywhere so I don't have to
think about this again.  Thanks,

Signed-off-by: Josef Bacik 
Signed-off-by: Jens Axboe 
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

zram: do not use copy_page with non-page aligned address

2017-04-21T07:31:22+00:00

commit d72e9a7a93e4f8e9e52491921d99e0c8aa89eb4e upstream.

The copy_page is optimized memcpy for page-alinged address.  If it is
used with non-page aligned address, it can corrupt memory which means
system corruption.  With zram, it can happen with

1. 64K architecture
2. partial IO
3. slub debug

Partial IO need to allocate a page and zram allocates it via kmalloc.
With slub debug, kmalloc(PAGE_SIZE) doesn't return page-size aligned
address.  And finally, copy_page(mem, cmem) corrupts memory.

So, this patch changes it to memcpy.

Actuaully, we don't need to change zram_bvec_write part because zsmalloc
returns page-aligned address in case of PAGE_SIZE class but it's not
good to rely on the internal of zsmalloc.

Note:
 When this patch is merged to stable, clear_page should be fixed, too.
 Unfortunately, recent zram removes it by "same page merge" feature so
 it's hard to backport this patch to -stable tree.

I will handle it when I receive the mail from stable tree maintainer to
merge this patch to backport.

Fixes: 42e99bd ("zram: optimize memory operations with clear_page()/copy_page()")
Link: http://lkml.kernel.org/r/1492042622-12074-2-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim 
Cc: Sergey Senozhatsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

loop: fix LO_FLAGS_PARTSCAN hang

2017-03-12T05:41:45+00:00

commit e02898b423802b1f3a3aaa7f16e896da069ba8f7 upstream.

loop_reread_partitions() needs to do I/O, but we just froze the queue,
so we end up waiting forever. This can easily be reproduced with losetup
-P. Fix it by moving the reread to after we unfreeze the queue.

Fixes: ecdd09597a57 ("block/loop: fix race between I/O and set_status")
Reported-by: Tejun Heo 
Signed-off-by: Omar Sandoval 
Reviewed-by: Ming Lei 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block/loop: fix race between I/O and set_status

2017-03-12T05:41:45+00:00

commit ecdd09597a57251323b0de50e3d45e69298c4a83 upstream.

Inside set_status, transfer need to setup again, so
we have to drain IO before the transition, otherwise
oops may be triggered like the following:

	divide error: 0000 [#1] SMP KASAN
	CPU: 0 PID: 2935 Comm: loop7 Not tainted 4.10.0-rc7+ #213
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
	01/01/2011
	task: ffff88006ba1e840 task.stack: ffff880067338000
	RIP: 0010:transfer_xor+0x1d1/0x440 drivers/block/loop.c:110
	RSP: 0018:ffff88006733f108 EFLAGS: 00010246
	RAX: 0000000000000000 RBX: ffff8800688d7000 RCX: 0000000000000059
	RDX: 0000000000000000 RSI: 1ffff1000d743f43 RDI: ffff880068891c08
	RBP: ffff88006733f160 R08: ffff8800688d7001 R09: 0000000000000000
	R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800688d7000
	R13: ffff880067b7d000 R14: dffffc0000000000 R15: 0000000000000000
	FS:  0000000000000000(0000) GS:ffff88006d000000(0000)
	knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 00000000006c17e0 CR3: 0000000066e3b000 CR4: 00000000001406f0
	Call Trace:
	 lo_do_transfer drivers/block/loop.c:251 [inline]
	 lo_read_transfer drivers/block/loop.c:392 [inline]
	 do_req_filebacked drivers/block/loop.c:541 [inline]
	 loop_handle_cmd drivers/block/loop.c:1677 [inline]
	 loop_queue_work+0xda0/0x49b0 drivers/block/loop.c:1689
	 kthread_worker_fn+0x4c3/0xa30 kernel/kthread.c:630
	 kthread+0x326/0x3f0 kernel/kthread.c:227
	 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430
	Code: 03 83 e2 07 41 29 df 42 0f b6 04 30 4d 8d 44 24 01 38 d0 7f 08
	84 c0 0f 85 62 02 00 00 44 89 f8 41 0f b6 48 ff 25 ff 01 00 00 99 
	7d c8 48 63 d2 48 03 55 d0 48 89 d0 48 89 d7 48 c1 e8 03 83
	RIP: transfer_xor+0x1d1/0x440 drivers/block/loop.c:110 RSP:
	ffff88006733f108
	---[ end trace 0166f7bd3b0c0933 ]---

Reported-by: Dmitry Vyukov 
Signed-off-by: Ming Lei 
Tested-by: Dmitry Vyukov 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

virtio_blk: avoid DMA to stack for the sense buffer

2017-01-19T19:18:03+00:00

commit a14d749fcebe97ddf6af6db3d1f6ece85c9ddcb9 upstream.

Most users of BLOCK_PC requests allocate the sense buffer on the stack,
so to avoid DMA to the stack copy them to a field in the heap allocated
virtblk_req structure.  Without that any attempt at SCSI passthrough I/O,
including the SG_IO ioctl from userspace will crash the kernel.  Note that
this includes running tools like hdparm even when the host does not have
SCSI passthrough enabled.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

zram: support BDI_CAP_STABLE_WRITES

2017-01-19T19:17:58+00:00

commit b09ab054b69b07077bd3292f67e777861ac796e5 upstream.

zram has used per-cpu stream feature from v4.7.  It aims for increasing
cache hit ratio of scratch buffer for compressing.  Downside of that
approach is that zram should ask memory space for compressed page in
per-cpu context which requires stricted gfp flag which could be failed.
If so, it retries to allocate memory space out of per-cpu context so it
could get memory this time and compress the data again, copies it to the
memory space.

In this scenario, zram assumes the data should never be changed but it is
not true without stable page support.  So, If the data is changed under
us, zram can make buffer overrun so that zsmalloc free object chain is
broken so system goes crash like below

   https://bugzilla.suse.com/show_bug.cgi?id=997574

This patch adds BDI_CAP_STABLE_WRITES to zram for declaring "I am block
device needing *stable write*".

Fixes: da9556a2367c ("zram: user per-cpu compression streams")
Link: http://lkml.kernel.org/r/1482366980-3782-4-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim 
Reviewed-by: Sergey Senozhatsky 
Cc: Takashi Iwai 
Cc: Hyeoncheol Lee 
Cc: 
Cc: Sangseok Lee 
Cc: Hugh Dickins 
Cc: Darrick J. Wong 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

zram: revalidate disk under init_lock

2017-01-19T19:17:58+00:00

commit e7ccfc4ccb703e0f033bd4617580039898e912dd upstream.

Commit b4c5c60920e3 ("zram: avoid lockdep splat by revalidate_disk")
moved revalidate_disk call out of init_lock to avoid lockdep
false-positive splat.  However, commit 08eee69fcf6b ("zram: remove
init_lock in zram_make_request") removed init_lock in IO path so there
is no worry about lockdep splat.  So, let's restore it.

This patch is needed to set BDI_CAP_STABLE_WRITES atomically in next
patch.

Fixes: da9556a2367c ("zram: user per-cpu compression streams")
Link: http://lkml.kernel.org/r/1482366980-3782-3-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim 
Reviewed-by: Sergey Senozhatsky 
Cc: Takashi Iwai 
Cc: Hyeoncheol Lee 
Cc: 
Cc: Sangseok Lee 
Cc: Hugh Dickins 
Cc: Darrick J. Wong 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

loop: return proper error from loop_queue_rq()

2017-01-06T09:40:14+00:00

commit b4a567e8114327518c09f5632339a5954ab975a3 upstream.

->queue_rq() should return one of the BLK_MQ_RQ_QUEUE_* constants, not
an errno.

Fixes: f4aa4c7bbac6 ("block: loop: convert to per-device workqueue")
Signed-off-by: Omar Sandoval 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

zram: restrict add/remove attributes to root only

2016-12-08T01:10:00+00:00

zram hot_add sysfs attribute is a very 'special' attribute - reading
from it creates a new uninitialized zram device.  This file, by a
mistake, can be read by a 'normal' user at the moment, while only root
must be able to create a new zram device, therefore hot_add attribute
must have S_IRUSR mode, not S_IRUGO.

[akpm@linux-foundation.org: s/sence/sense/, reflow comment to use 80 cols]
Fixes: 6566d1a32bf72 ("zram: add dynamic device add/remove functionality")
Link: http://lkml.kernel.org/r/20161205155845.20129-1-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky 
Reported-by: Steven Allen 
Acked-by: Greg Kroah-Hartman 
Cc: Minchan Kim 
Cc:     [4.2+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds