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Linux kernel
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Pull SCSI fixes from James Bottomley:
"Eight fixes.
The most important one is the mpt3sas fix which makes the driver work
again on big endian systems. The rest are mostly minor error path or
checker issues and the vmw_scsi one fixes a performance problem"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: vmw_pvscsi: Return DID_RESET for status SAM_STAT_COMMAND_TERMINATED
scsi: sr: Avoid that opening a CD-ROM hangs with runtime power management enabled
scsi: mpt3sas: Swap I/O memory read value back to cpu endianness
scsi: fcoe: clear FC_RP_STARTED flags when receiving a LOGO
scsi: fcoe: drop frames in ELS LOGO error path
scsi: fcoe: fix use-after-free in fcoe_ctlr_els_send
scsi: qedi: Fix a potential buffer overflow
scsi: qla2xxx: Fix memory leak for allocating abort IOCB
This is purely a preparatory patch for upcoming changes during the 4.19
merge window.
We have a function called "boot_cpu_state_init()" that isn't really
about the bootup cpu state: that is done much earlier by the similarly
named "boot_cpu_init()" (note lack of "state" in name).
This function initializes some hotplug CPU state, and needs to run after
the percpu data has been properly initialized. It even has a comment to
that effect.
Except it _doesn't_ actually run after the percpu data has been properly
initialized. On x86 it happens to do that, but on at least arm and
arm64, the percpu base pointers are initialized by the arch-specific
'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().
This had some unexpected results, and in particular we have a patch
pending for the merge window that did the obvious cleanup of using
'this_cpu_write()' in the cpu hotplug init code:
- per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
+ this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);
which is obviously the right thing to do. Except because of the
ordering issue, it actually failed miserably and unexpectedly on arm64.
So this just fixes the ordering, and changes the name of the function to
be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
hotplug state, because the core CPU state was supposed to have already
been done earlier.
Marked for stable, since the (not yet merged) patch that will show this
problem is marked for stable.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commands that are reset are returned with status
SAM_STAT_COMMAND_TERMINATED. PVSCSI currently returns DID_OK |
SAM_STAT_COMMAND_TERMINATED which fails the command. Instead, set hostbyte
to DID_RESET to allow upper layers to retry.
Tested by copying a large file between two pvscsi disks on same adapter
while performing a bus reset at 1-second intervals. Before fix, commands
sometimes fail with DID_OK. After fix, commands observed to fail with
DID_RESET.
Signed-off-by: Jim Gill <jgill@vmware.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull vfs fixes from Al Viro:
"A bunch of race fixes, mostly around lazy pathwalk.
All of it is -stable fodder, a large part going back to 2013"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
make sure that __dentry_kill() always invalidates d_seq, unhashed or not
fix __legitimize_mnt()/mntput() race
fix mntput/mntput race
root dentries need RCU-delayed freeing
Surround scsi_execute() calls with scsi_autopm_get_device() and
scsi_autopm_put_device(). Note: removing sr_mutex protection from the
scsi_cd_get() and scsi_cd_put() calls is safe because the purpose of
sr_mutex is to serialize cdrom_*() calls.
This patch avoids that complaints similar to the following appear in the
kernel log if runtime power management is enabled:
INFO: task systemd-udevd:650 blocked for more than 120 seconds.
Not tainted 4.18.0-rc7-dbg+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
systemd-udevd D28176 650 513 0x00000104
Call Trace:
__schedule+0x444/0xfe0
schedule+0x4e/0xe0
schedule_preempt_disabled+0x18/0x30
__mutex_lock+0x41c/0xc70
mutex_lock_nested+0x1b/0x20
__blkdev_get+0x106/0x970
blkdev_get+0x22c/0x5a0
blkdev_open+0xe9/0x100
do_dentry_open.isra.19+0x33e/0x570
vfs_open+0x7c/0xd0
path_openat+0x6e3/0x1120
do_filp_open+0x11c/0x1c0
do_sys_open+0x208/0x2d0
__x64_sys_openat+0x59/0x70
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull networking fixes from David Miller:
"Last bit of straggler fixes...
1) Fix btf library licensing to LGPL, from Martin KaFai lau.
2) Fix error handling in bpf sockmap code, from Daniel Borkmann.
3) XDP cpumap teardown handling wrt. execution contexts, from Jesper
Dangaard Brouer.
4) Fix loss of runtime PM on failed vlan add/del, from Ivan
Khoronzhuk.
5) xen-netfront caches skb_shinfo(skb) across a __pskb_pull_tail()
call, which potentially changes the skb's data buffer, and thus
skb_shinfo(). Fix from Juergen Gross"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
xen/netfront: don't cache skb_shinfo()
net: ethernet: ti: cpsw: fix runtime_pm while add/kill vlan
net: ethernet: ti: cpsw: clear all entries when delete vid
xdp: fix bug in devmap teardown code path
samples/bpf: xdp_redirect_cpu adjustment to reproduce teardown race easier
xdp: fix bug in cpumap teardown code path
bpf, sockmap: fix cork timeout for select due to epipe
bpf, sockmap: fix leak in bpf_tcp_sendmsg wait for mem path
bpf, sockmap: fix bpf_tcp_sendmsg sock error handling
bpf: btf: Change tools/lib/bpf/btf to LGPL
RCU pathwalk relies upon the assumption that anything that changes
->d_inode of a dentry will invalidate its ->d_seq. That's almost
true - the one exception is that the final dput() of already unhashed
dentry does *not* touch ->d_seq at all. Unhashing does, though,
so for anything we'd found by RCU dcache lookup we are fine.
Unfortunately, we can *start* with an unhashed dentry or jump into
it.
We could try and be careful in the (few) places where that could
happen. Or we could just make the final dput() invalidate the damn
thing, unhashed or not. The latter is much simpler and easier to
backport, so let's do it that way.
Reported-by: "Dae R. Jeong" <threeearcat@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Swap the I/O memory read value back to cpu endianness before storing it in
a data structures which are defined in the MPI headers where u8 components
are not defined in the endianness order.
In this area from day one mpt3sas driver is using le32_to_cpu() &
cpu_to_le32() APIs. But in commit cf6bf9710c
(mpt3sas: Bug fix for big endian systems) we have removed these APIs
before reading I/O memory which we should haven't done it. So
in this patch I am correcting it by adding these APIs back
before accessing I/O memory.
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If zram supports writeback feature, it's no longer a
BD_CAP_SYNCHRONOUS_IO device beause zram does asynchronous IO operations
for incompressible pages.
Do not pretend to be synchronous IO device. It makes the system very
sluggish due to waiting for IO completion from upper layers.
Furthermore, it causes a user-after-free problem because swap thinks the
opearion is done when the IO functions returns so it can free the page
(e.g., lock_page_or_retry and goto out_release in do_swap_page) but in
fact, IO is asynchronous so the driver could access a just freed page
afterward.
This patch fixes the problem.
BUG: Bad page state in process qemu-system-x86 pfn:3dfab21
page:ffffdfb137eac840 count:0 mapcount:0 mapping:0000000000000000 index:0x1
flags: 0x17fffc000000008(uptodate)
raw: 017fffc000000008 dead000000000100 dead000000000200 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
bad because of flags: 0x8(uptodate)
CPU: 4 PID: 1039 Comm: qemu-system-x86 Tainted: G B 4.18.0-rc5+ #1
Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0b 05/02/2017
Call Trace:
dump_stack+0x5c/0x7b
bad_page+0xba/0x120
get_page_from_freelist+0x1016/0x1250
__alloc_pages_nodemask+0xfa/0x250
alloc_pages_vma+0x7c/0x1c0
do_swap_page+0x347/0x920
__handle_mm_fault+0x7b4/0x1110
handle_mm_fault+0xfc/0x1f0
__get_user_pages+0x12f/0x690
get_user_pages_unlocked+0x148/0x1f0
__gfn_to_pfn_memslot+0xff/0x3c0 [kvm]
try_async_pf+0x87/0x230 [kvm]
tdp_page_fault+0x132/0x290 [kvm]
kvm_mmu_page_fault+0x74/0x570 [kvm]
kvm_arch_vcpu_ioctl_run+0x9b3/0x1990 [kvm]
kvm_vcpu_ioctl+0x388/0x5d0 [kvm]
do_vfs_ioctl+0xa2/0x630
ksys_ioctl+0x70/0x80
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x55/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
[minchan@kernel.org: fix changelog, add comment]
Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180805233722.217347-1-minchan@kernel.org
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Tino Lehnig <tino.lehnig@contabo.de>
Tested-by: Tino Lehnig <tino.lehnig@contabo.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org> [4.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
skb_shinfo() can change when calling __pskb_pull_tail(): Don't cache
its return value.
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__legitimize_mnt() has two problems - one is that in case of success
the check of mount_lock is not ordered wrt preceding increment of
refcount, making it possible to have successful __legitimize_mnt()
on one CPU just before the otherwise final mntpu() on another,
with __legitimize_mnt() not seeing mntput() taking the lock and
mntput() not seeing the increment done by __legitimize_mnt().
Solved by a pair of barriers.
Another is that failure of __legitimize_mnt() on the second
read_seqretry() leaves us with reference that'll need to be
dropped by caller; however, if that races with final mntput()
we can end up with caller dropping rcu_read_lock() and doing
mntput() to release that reference - with the first mntput()
having freed the damn thing just as rcu_read_lock() had been
dropped. Solution: in "do mntput() yourself" failure case
grab mount_lock, check if MNT_DOOMED has been set by racing
final mntput() that has missed our increment and if it has -
undo the increment and treat that as "failure, caller doesn't
need to drop anything" case.
It's not easy to hit - the final mntput() has to come right
after the first read_seqretry() in __legitimize_mnt() *and*
manage to miss the increment done by __legitimize_mnt() before
the second read_seqretry() in there. The things that are almost
impossible to hit on bare hardware are not impossible on SMP
KVM, though...
Reported-by: Oleg Nesterov <oleg@redhat.com>
Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When receiving a LOGO request we forget to clear the FC_RP_STARTED flag
before starting the rport delete routine.
As the started flag was not cleared, we're not deleting the rport but
waiting for a restart and thus are keeping the reference count of the rdata
object at 1.
This leads to the following kmemleak report:
unreferenced object 0xffff88006542aa00 (size 512):
comm "kworker/0:2", pid 24, jiffies 4294899222 (age 226.880s)
hex dump (first 32 bytes):
68 96 fe 65 00 88 ff ff 00 00 00 00 00 00 00 00 h..e............
01 00 00 00 08 00 00 00 02 c5 45 24 ac b8 00 10 ..........E$....
backtrace:
[<(____ptrval____)>] fcoe_ctlr_vn_add.isra.5+0x7f/0x770 [libfcoe]
[<(____ptrval____)>] fcoe_ctlr_vn_recv+0x12af/0x27f0 [libfcoe]
[<(____ptrval____)>] fcoe_ctlr_recv_work+0xd01/0x32f0 [libfcoe]
[<(____ptrval____)>] process_one_work+0x7ff/0x1420
[<(____ptrval____)>] worker_thread+0x87/0xef0
[<(____ptrval____)>] kthread+0x2db/0x390
[<(____ptrval____)>] ret_from_fork+0x35/0x40
[<(____ptrval____)>] 0xffffffffffffffff
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: ard <ard@kwaak.net>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
ioremap_prot() can return NULL which could lead to an oops.
Link: http://lkml.kernel.org/r/1533195441-58594-1-git-send-email-chenjie6@huawei.com
Signed-off-by: chen jie <chenjie6@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: chenjie <chenjie6@huawei.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Grygorii Strashko says:
====================
net: ethernet: ti: cpsw: fix runtime pm while add/del reserved vid
Here 2 not critical fixes for:
- vlan ale table leak while error if deleting vlan (simplifies next fix)
- runtime pm while try to set reserved vlan
====================
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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