linux_dsm_epyc7002/drivers/block
Vitaly Kuznetsov 12ea729645 xen/blkback: unmap all persistent grants when frontend gets disconnected
blkback does not unmap persistent grants when frontend goes to Closed
state (e.g. when blkfront module is being removed). This leads to the
following in guest's dmesg:

[  343.243825] xen:grant_table: WARNING: g.e. 0x445 still in use!
[  343.243825] xen:grant_table: WARNING: g.e. 0x42a still in use!
...

When load module -> use device -> unload module sequence is performed multiple times
it is possible to hit BUG() condition in blkfront module:

[  343.243825] kernel BUG at drivers/block/xen-blkfront.c:954!
[  343.243825] invalid opcode: 0000 [#1] SMP
[  343.243825] Modules linked in: xen_blkfront(-) ata_generic pata_acpi [last unloaded: xen_blkfront]
...
[  343.243825] Call Trace:
[  343.243825]  [<ffffffff814111ef>] ? unregister_xenbus_watch+0x16f/0x1e0
[  343.243825]  [<ffffffffa0016fbf>] blkfront_remove+0x3f/0x140 [xen_blkfront]
...
[  343.243825] RIP  [<ffffffffa0016aae>] blkif_free+0x34e/0x360 [xen_blkfront]
[  343.243825]  RSP <ffff88001eb8fdc0>

We don't need to keep these grants if we're disconnecting as frontend might already
forgot about them. Solve the issue by moving xen_blkbk_free_caches() call from
xen_blkif_free() to xen_blkif_disconnect().

Now we can see the following:
[  928.590893] xen:grant_table: WARNING: g.e. 0x587 still in use!
[  928.591861] xen:grant_table: WARNING: g.e. 0x372 still in use!
...
[  929.592146] xen:grant_table: freeing g.e. 0x587
[  929.597174] xen:grant_table: freeing g.e. 0x372
...

Backend does not keep persistent grants any more, reconnect works fine.

CC: stable@vger.kernel.org
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-10-01 16:32:23 -04:00
..
aoe mm: close PageTail race 2014-03-04 07:55:47 -08:00
drbd drbd: use RB_DECLARE_CALLBACKS() to define augment callbacks 2014-09-18 09:00:17 -06:00
mtip32xx PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use 2014-08-12 12:15:14 -06:00
paride block,scsi: fixup blk_get_request dead queue scenarios 2014-08-28 10:03:46 -06:00
rsxx PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use 2014-08-12 12:15:14 -06:00
xen-blkback xen/blkback: unmap all persistent grants when frontend gets disconnected 2014-10-01 16:32:23 -04:00
zram zram: replace global tb_lock with fine grain lock 2014-08-06 18:01:23 -07:00
amiflop.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
ataflop.c Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into next 2014-06-02 09:29:34 -07:00
brd.c brd: return -ENOSPC rather than -ENOMEM on page allocation failure 2014-06-04 16:54:02 -07:00
cciss_cmd.h cciss: use new doorbell-bit-5 reset method 2011-05-06 08:23:55 -06:00
cciss_scsi.c cciss: switch to ->show_info() 2013-04-09 14:13:19 -04:00
cciss_scsi.h cciss: add cciss_tape_cmds module paramter 2011-05-06 08:23:59 -06:00
cciss.c block: use pci_zalloc_consistent 2014-08-08 15:57:28 -07:00
cciss.h cciss: Adds simple mode functionality 2011-08-08 11:40:15 +02:00
cpqarray.c cpqarray: fix info leak in ida_locked_ioctl() 2013-09-24 17:00:26 -07:00
cpqarray.h
cryptoloop.c move linux/loop.h to drivers/block 2013-06-29 12:46:45 +04:00
DAC960.c block: use pci_zalloc_consistent 2014-08-08 15:57:28 -07:00
DAC960.h
floppy.c Merge branch 'for-jens' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/linux-block into for-linus 2014-06-18 10:30:22 -07:00
hd.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
ida_cmd.h
ida_ioctl.h
Kconfig zram: promote zram from staging 2014-01-30 16:56:55 -08:00
loop.c Merge branch 'sched/urgent' into sched/core, to avoid conflicts 2014-05-07 13:15:46 +02:00
loop.h move linux/loop.h to drivers/block 2013-06-29 12:46:45 +04:00
Makefile zram: promote zram from staging 2014-01-30 16:56:55 -08:00
mg_disk.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
nbd.c nbd: zero from and len fields in NBD_CMD_DISCONNECT. 2014-06-06 16:08:18 -07:00
null_blk.c null_blk: fix softirq completions for queue_mode == 1 2014-06-16 11:40:25 -06:00
nvme-core.c Merge git://git.infradead.org/users/willy/linux-nvme 2014-06-15 15:58:03 -10:00
nvme-scsi.c NVMe: Fix START_STOP_UNIT Scsi->NVMe translation. 2014-06-13 13:11:00 -04:00
osdblk.c block: replace strict_strtoul() with kstrtoul() 2013-09-11 15:56:56 -07:00
pktcdvd.c block,scsi: fixup blk_get_request dead queue scenarios 2014-08-28 10:03:46 -06:00
ps3disk.c block: Kill bio_segments()/bi_vcnt usage 2013-11-23 22:33:51 -08:00
ps3vram.c block: Convert bio_for_each_segment() to bvec_iter 2013-11-23 22:33:49 -08:00
rbd_types.h rbd: get rid of RBD_MAX_SEG_NAME_LEN 2012-12-17 08:37:29 -06:00
rbd.c rbd: remove extra newlines from rbd_warn() messages 2014-08-07 16:01:09 +04:00
skd_main.c PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use 2014-08-12 12:15:14 -06:00
skd_s1120.h skd: fix formatting in skd_s1120.h 2013-11-08 09:10:30 -07:00
smart1,2.h fix typos 'comamnd' -> 'command' in comments 2011-02-02 11:31:21 +01:00
sunvdc.c sunvdc: Fix off-by-one in generic_request(). 2013-02-14 11:49:01 -08:00
swim3.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
swim_asm.S
swim.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
sx8.c block,scsi: fixup blk_get_request dead queue scenarios 2014-08-28 10:03:46 -06:00
umem.c block: Convert drivers to immutable biovecs 2013-11-23 22:33:51 -08:00
umem.h
virtio_blk.c block: virtio-blk: support multi virt queues per virtio-blk device 2014-07-01 10:51:03 -06:00
xen-blkfront.c Merge branch 'stable/for-jens-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip into for-3.16/drivers 2014-05-28 12:37:04 -06:00
xsysace.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00
z2ram.c block: remove struct request buffer member 2014-04-15 14:03:02 -06:00