--- /dev/null
+From 1e047eaab3bb5564f25b41e9cd3a053009f4e789 Mon Sep 17 00:00:00 2001
+From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
+Date: Fri, 6 Apr 2018 10:03:17 +0900
+Subject: block/loop: fix deadlock after loop_set_status
+
+From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
+
+commit 1e047eaab3bb5564f25b41e9cd3a053009f4e789 upstream.
+
+syzbot is reporting deadlocks at __blkdev_get() [1].
+
+----------------------------------------
+[ 92.493919] systemd-udevd D12696 525 1 0x00000000
+[ 92.495891] Call Trace:
+[ 92.501560] schedule+0x23/0x80
+[ 92.502923] schedule_preempt_disabled+0x5/0x10
+[ 92.504645] __mutex_lock+0x416/0x9e0
+[ 92.510760] __blkdev_get+0x73/0x4f0
+[ 92.512220] blkdev_get+0x12e/0x390
+[ 92.518151] do_dentry_open+0x1c3/0x2f0
+[ 92.519815] path_openat+0x5d9/0xdc0
+[ 92.521437] do_filp_open+0x7d/0xf0
+[ 92.527365] do_sys_open+0x1b8/0x250
+[ 92.528831] do_syscall_64+0x6e/0x270
+[ 92.530341] entry_SYSCALL_64_after_hwframe+0x42/0xb7
+
+[ 92.931922] 1 lock held by systemd-udevd/525:
+[ 92.933642] #0: 00000000a2849e25 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x73/0x4f0
+----------------------------------------
+
+The reason of deadlock turned out that wait_event_interruptible() in
+blk_queue_enter() got stuck with bdev->bd_mutex held at __blkdev_put()
+due to q->mq_freeze_depth == 1.
+
+----------------------------------------
+[ 92.787172] a.out S12584 634 633 0x80000002
+[ 92.789120] Call Trace:
+[ 92.796693] schedule+0x23/0x80
+[ 92.797994] blk_queue_enter+0x3cb/0x540
+[ 92.803272] generic_make_request+0xf0/0x3d0
+[ 92.807970] submit_bio+0x67/0x130
+[ 92.810928] submit_bh_wbc+0x15e/0x190
+[ 92.812461] __block_write_full_page+0x218/0x460
+[ 92.815792] __writepage+0x11/0x50
+[ 92.817209] write_cache_pages+0x1ae/0x3d0
+[ 92.825585] generic_writepages+0x5a/0x90
+[ 92.831865] do_writepages+0x43/0xd0
+[ 92.836972] __filemap_fdatawrite_range+0xc1/0x100
+[ 92.838788] filemap_write_and_wait+0x24/0x70
+[ 92.840491] __blkdev_put+0x69/0x1e0
+[ 92.841949] blkdev_close+0x16/0x20
+[ 92.843418] __fput+0xda/0x1f0
+[ 92.844740] task_work_run+0x87/0xb0
+[ 92.846215] do_exit+0x2f5/0xba0
+[ 92.850528] do_group_exit+0x34/0xb0
+[ 92.852018] SyS_exit_group+0xb/0x10
+[ 92.853449] do_syscall_64+0x6e/0x270
+[ 92.854944] entry_SYSCALL_64_after_hwframe+0x42/0xb7
+
+[ 92.943530] 1 lock held by a.out/634:
+[ 92.945105] #0: 00000000a2849e25 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0x3c/0x1e0
+----------------------------------------
+
+The reason of q->mq_freeze_depth == 1 turned out that loop_set_status()
+forgot to call blk_mq_unfreeze_queue() at error paths for
+info->lo_encrypt_type != NULL case.
+
+----------------------------------------
+[ 37.509497] CPU: 2 PID: 634 Comm: a.out Tainted: G W 4.16.0+ #457
+[ 37.513608] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
+[ 37.518832] RIP: 0010:blk_freeze_queue_start+0x17/0x40
+[ 37.521778] RSP: 0018:ffffb0c2013e7c60 EFLAGS: 00010246
+[ 37.524078] RAX: 0000000000000000 RBX: ffff8b07b1519798 RCX: 0000000000000000
+[ 37.527015] RDX: 0000000000000002 RSI: ffffb0c2013e7cc0 RDI: ffff8b07b1519798
+[ 37.529934] RBP: ffffb0c2013e7cc0 R08: 0000000000000008 R09: 47a189966239b898
+[ 37.532684] R10: dad78b99b278552f R11: 9332dca72259d5ef R12: ffff8b07acd73678
+[ 37.535452] R13: 0000000000004c04 R14: 0000000000000000 R15: ffff8b07b841e940
+[ 37.538186] FS: 00007fede33b9740(0000) GS:ffff8b07b8e80000(0000) knlGS:0000000000000000
+[ 37.541168] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
+[ 37.543590] CR2: 00000000206fdf18 CR3: 0000000130b30006 CR4: 00000000000606e0
+[ 37.546410] Call Trace:
+[ 37.547902] blk_freeze_queue+0x9/0x30
+[ 37.549968] loop_set_status+0x67/0x3c0 [loop]
+[ 37.549975] loop_set_status64+0x3b/0x70 [loop]
+[ 37.549986] lo_ioctl+0x223/0x810 [loop]
+[ 37.549995] blkdev_ioctl+0x572/0x980
+[ 37.550003] block_ioctl+0x34/0x40
+[ 37.550006] do_vfs_ioctl+0xa7/0x6d0
+[ 37.550017] ksys_ioctl+0x6b/0x80
+[ 37.573076] SyS_ioctl+0x5/0x10
+[ 37.574831] do_syscall_64+0x6e/0x270
+[ 37.576769] entry_SYSCALL_64_after_hwframe+0x42/0xb7
+----------------------------------------
+
+[1] https://syzkaller.appspot.com/bug?id=cd662bc3f6022c0979d01a262c318fab2ee9b56f
+
+Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
+Reported-by: syzbot <bot+48594378e9851eab70bcd6f99327c7db58c5a28a@syzkaller.appspotmail.com>
+Fixes: ecdd09597a572513 ("block/loop: fix race between I/O and set_status")
+Cc: Ming Lei <tom.leiming@gmail.com>
+Cc: Dmitry Vyukov <dvyukov@google.com>
+Cc: stable <stable@vger.kernel.org>
+Cc: Jens Axboe <axboe@fb.com>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/block/loop.c | 12 ++++++++----
+ 1 file changed, 8 insertions(+), 4 deletions(-)
+
+--- a/drivers/block/loop.c
++++ b/drivers/block/loop.c
+@@ -1086,11 +1086,15 @@ loop_set_status(struct loop_device *lo,
+ if (info->lo_encrypt_type) {
+ unsigned int type = info->lo_encrypt_type;
+
+- if (type >= MAX_LO_CRYPT)
+- return -EINVAL;
++ if (type >= MAX_LO_CRYPT) {
++ err = -EINVAL;
++ goto exit;
++ }
+ xfer = xfer_funcs[type];
+- if (xfer == NULL)
+- return -EINVAL;
++ if (xfer == NULL) {
++ err = -EINVAL;
++ goto exit;
++ }
+ } else
+ xfer = NULL;
+
--- /dev/null
+From 15deb080a6087b73089139569558965750e69d67 Mon Sep 17 00:00:00 2001
+From: Vasily Gorbik <gor@linux.ibm.com>
+Date: Tue, 3 Apr 2018 16:02:15 +0200
+Subject: s390/ipl: ensure loadparm valid flag is set
+
+From: Vasily Gorbik <gor@linux.ibm.com>
+
+commit 15deb080a6087b73089139569558965750e69d67 upstream.
+
+When loadparm is set in reipl parm block, the kernel should also set
+DIAG308_FLAGS_LP_VALID flag.
+
+This fixes loadparm ignoring during z/VM fcp -> ccw reipl and kvm direct
+boot -> ccw reipl.
+
+Cc: <stable@vger.kernel.org>
+Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
+Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
+Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/s390/kernel/ipl.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/arch/s390/kernel/ipl.c
++++ b/arch/s390/kernel/ipl.c
+@@ -808,6 +808,7 @@ static ssize_t reipl_generic_loadparm_st
+ /* copy and convert to ebcdic */
+ memcpy(ipb->hdr.loadparm, buf, lp_len);
+ ASCEBC(ipb->hdr.loadparm, LOADPARM_LEN);
++ ipb->hdr.flags |= DIAG308_FLAGS_LP_VALID;
+ return len;
+ }
+
--- /dev/null
+From 0cf1e05157b9e5530dcc3ca9fec9bf617fc93375 Mon Sep 17 00:00:00 2001
+From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+Date: Wed, 7 Mar 2018 14:01:01 +0100
+Subject: s390/qdio: don't merge ERROR output buffers
+
+From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+
+commit 0cf1e05157b9e5530dcc3ca9fec9bf617fc93375 upstream.
+
+On an Output queue, both EMPTY and PENDING buffer states imply that the
+buffer is ready for completion-processing by the upper-layer drivers.
+
+So for a non-QEBSM Output queue, get_buf_states() merges mixed
+batches of PENDING and EMPTY buffers into one large batch of EMPTY
+buffers. The upper-layer driver (ie. qeth) later distuingishes PENDING
+from EMPTY by inspecting the slsb_state for
+QDIO_OUTBUF_STATE_FLAG_PENDING.
+
+But the merge logic in get_buf_states() contains a bug that causes us to
+erronously also merge ERROR buffers into such a batch of EMPTY buffers
+(ERROR is 0xaf, EMPTY is 0xa1; so ERROR & EMPTY == EMPTY).
+Effectively, most outbound ERROR buffers are currently discarded
+silently and processed as if they had succeeded.
+
+Note that this affects _all_ non-QEBSM device types, not just IQD with CQ.
+
+Fix it by explicitly spelling out the exact conditions for merging.
+
+For extracting the "get initial state" part out of the loop, this relies
+on the fact that get_buf_states() is never called with a count of 0. The
+QEBSM path already strictly requires this, and the two callers with
+variable 'count' make sure of it.
+
+Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks")
+Cc: <stable@vger.kernel.org> #v3.2+
+Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
+Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
+Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/s390/cio/qdio_main.c | 31 ++++++++++++++++++++-----------
+ 1 file changed, 20 insertions(+), 11 deletions(-)
+
+--- a/drivers/s390/cio/qdio_main.c
++++ b/drivers/s390/cio/qdio_main.c
+@@ -205,7 +205,10 @@ again:
+ return 0;
+ }
+
+-/* returns number of examined buffers and their common state in *state */
++/*
++ * Returns number of examined buffers and their common state in *state.
++ * Requested number of buffers-to-examine must be > 0.
++ */
+ static inline int get_buf_states(struct qdio_q *q, unsigned int bufnr,
+ unsigned char *state, unsigned int count,
+ int auto_ack, int merge_pending)
+@@ -216,17 +219,23 @@ static inline int get_buf_states(struct
+ if (is_qebsm(q))
+ return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
+
+- for (i = 0; i < count; i++) {
+- if (!__state) {
+- __state = q->slsb.val[bufnr];
+- if (merge_pending && __state == SLSB_P_OUTPUT_PENDING)
+- __state = SLSB_P_OUTPUT_EMPTY;
+- } else if (merge_pending) {
+- if ((q->slsb.val[bufnr] & __state) != __state)
+- break;
+- } else if (q->slsb.val[bufnr] != __state)
+- break;
++ /* get initial state: */
++ __state = q->slsb.val[bufnr];
++ if (merge_pending && __state == SLSB_P_OUTPUT_PENDING)
++ __state = SLSB_P_OUTPUT_EMPTY;
++
++ for (i = 1; i < count; i++) {
+ bufnr = next_buf(bufnr);
++
++ /* merge PENDING into EMPTY: */
++ if (merge_pending &&
++ q->slsb.val[bufnr] == SLSB_P_OUTPUT_PENDING &&
++ __state == SLSB_P_OUTPUT_EMPTY)
++ continue;
++
++ /* stop if next state differs from initial state: */
++ if (q->slsb.val[bufnr] != __state)
++ break;
+ }
+ *state = __state;
+ return i;
--- /dev/null
+From dae55b6fef58530c13df074bcc182c096609339e Mon Sep 17 00:00:00 2001
+From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+Date: Mon, 5 Mar 2018 09:39:38 +0100
+Subject: s390/qdio: don't retry EQBS after CCQ 96
+
+From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+
+commit dae55b6fef58530c13df074bcc182c096609339e upstream.
+
+Immediate retry of EQBS after CCQ 96 means that we potentially misreport
+the state of buffers inspected during the first EQBS call.
+
+This occurs when
+1. the first EQBS finds all inspected buffers still in the initial state
+ set by the driver (ie INPUT EMPTY or OUTPUT PRIMED),
+2. the EQBS terminates early with CCQ 96, and
+3. by the time that the second EQBS comes around, the state of those
+ previously inspected buffers has changed.
+
+If the state reported by the second EQBS is 'driver-owned', all we know
+is that the previous buffers are driver-owned now as well. But we can't
+tell if they all have the same state. So for instance
+- the second EQBS reports OUTPUT EMPTY, but any number of the previous
+ buffers could be OUTPUT ERROR by now,
+- the second EQBS reports OUTPUT ERROR, but any number of the previous
+ buffers could be OUTPUT EMPTY by now.
+
+Effectively, this can result in both over- and underreporting of errors.
+
+If the state reported by the second EQBS is 'HW-owned', that doesn't
+guarantee that the previous buffers have not been switched to
+driver-owned in the mean time. So for instance
+- the second EQBS reports INPUT EMPTY, but any number of the previous
+ buffers could be INPUT PRIMED (or INPUT ERROR) by now.
+
+This would result in failure to process pending work on the queue. If
+it's the final check before yielding initiative, this can cause
+a (temporary) queue stall due to IRQ avoidance.
+
+Fixes: 25f269f17316 ("[S390] qdio: EQBS retry after CCQ 96")
+Cc: <stable@vger.kernel.org> #v3.2+
+Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
+Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
+Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/s390/cio/qdio_main.c | 11 ++---------
+ 1 file changed, 2 insertions(+), 9 deletions(-)
+
+--- a/drivers/s390/cio/qdio_main.c
++++ b/drivers/s390/cio/qdio_main.c
+@@ -126,7 +126,7 @@ static inline int qdio_check_ccq(struct
+ static int qdio_do_eqbs(struct qdio_q *q, unsigned char *state,
+ int start, int count, int auto_ack)
+ {
+- int rc, tmp_count = count, tmp_start = start, nr = q->nr, retried = 0;
++ int rc, tmp_count = count, tmp_start = start, nr = q->nr;
+ unsigned int ccq = 0;
+
+ qperf_inc(q, eqbs);
+@@ -149,14 +149,7 @@ again:
+ qperf_inc(q, eqbs_partial);
+ DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS part:%02x",
+ tmp_count);
+- /*
+- * Retry once, if that fails bail out and process the
+- * extracted buffers before trying again.
+- */
+- if (!retried++)
+- goto again;
+- else
+- return count - tmp_count;
++ return count - tmp_count;
+ }
+
+ DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
media-v4l2-compat-ioctl32-don-t-oops-on-overlay.patch
parisc-fix-out-of-array-access-in-match_pci_device.patch
+block-loop-fix-deadlock-after-loop_set_status.patch
+s390-qdio-don-t-retry-eqbs-after-ccq-96.patch
+s390-qdio-don-t-merge-error-output-buffers.patch
+s390-ipl-ensure-loadparm-valid-flag-is-set.patch
projects / thirdparty / kernel / stable-queue.git / commitdiff
