I didn't receive any replies on this, and it doesn't seem to have made
it into the latest 3.18 or 4.4 releases. Previously sent on Aug 23rd:
https://lists.linaro.org/pipermail/linux-stable-mirror/2018-August/056347.h…
I assume I sent it wrong; maybe missing keywords or recipients? If
anyone can tell me what I missed, I'd appreciate it.
Trivial backport of commit 3e536e222f293053; newer kernels have simply
moved the vararg macros.
Testing: 3.18 and 4.4 booted OK in qemu.
>8------------------------------------------------------8<
[backport of commit 3e536e222f293053 from mainline]
There is a window for racing when printing directly to task->comm,
allowing other threads to see a non-terminated string. The vsnprintf
function fills the buffer, counts the truncated chars, then finally
writes the \0 at the end.
creator other
vsnprintf:
fill (not terminated)
count the rest trace_sched_waking(p):
... memcpy(comm, p->comm, TASK_COMM_LEN)
write \0
The consequences depend on how 'other' uses the string. In our case,
it was copied into the tracing system's saved cmdlines, a buffer of
adjacent TASK_COMM_LEN-byte buffers (note the 'n' where 0 should be):
crash-arm64> x/1024s savedcmd->saved_cmdlines | grep 'evenk'
0xffffffd5b3818640: "irq/497-pwr_evenkworker/u16:12"
...and a strcpy out of there would cause stack corruption:
[224761.522292] Kernel panic - not syncing: stack-protector:
Kernel stack is corrupted in: ffffff9bf9783c78
crash-arm64> kbt | grep 'comm\|trace_print_context'
#6 0xffffff9bf9783c78 in trace_print_context+0x18c(+396)
comm (char [16]) = "irq/497-pwr_even"
crash-arm64> rd 0xffffffd4d0e17d14 8
ffffffd4d0e17d14: 2f71726900000000 5f7277702d373934 ....irq/497-pwr_
ffffffd4d0e17d24: 726f776b6e657665 3a3631752f72656b evenkworker/u16:
ffffffd4d0e17d34: f9780248ff003231 cede60e0ffffff9b 12..H.x......`..
ffffffd4d0e17d44: cede60c8ffffffd4 00000fffffffffd4 .....`..........
The workaround in e09e28671 (use strlcpy in __trace_find_cmdline) was
likely needed because of this same bug.
Solved by vsnprintf:ing to a local buffer, then using set_task_comm().
This way, there won't be a window where comm is not terminated.
Cc: stable(a)vger.kernel.org
Fixes: bc0c38d139ec7 ("ftrace: latency tracer infrastructure")
Reviewed-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
[backported to 3.18 / 4.4 by Snild]
Signed-off-by: Snild Dolkow <snild(a)sony.com>
---
kernel/kthread.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 850b255..ac6849e 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -313,10 +313,16 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
task = create->result;
if (!IS_ERR(task)) {
static const struct sched_param param = { .sched_priority = 0 };
+ char name[TASK_COMM_LEN];
va_list args;
va_start(args, namefmt);
- vsnprintf(task->comm, sizeof(task->comm), namefmt, args);
+ /*
+ * task is already visible to other tasks, so updating
+ * COMM must be protected.
+ */
+ vsnprintf(name, sizeof(name), namefmt, args);
+ set_task_comm(task, name);
va_end(args);
/*
* root may have changed our (kthreadd's) priority or CPU mask.
--
2.7.4
Trivial backport of commit 3e536e222f293053; newer kernels have simply
moved the vararg macros.
Testing: 3.18 and 4.4 booted OK in qemu.
>8------------------------------------------------------8<
[backport of commit 3e536e222f293053 from mainline]
There is a window for racing when printing directly to task->comm,
allowing other threads to see a non-terminated string. The vsnprintf
function fills the buffer, counts the truncated chars, then finally
writes the \0 at the end.
creator other
vsnprintf:
fill (not terminated)
count the rest trace_sched_waking(p):
... memcpy(comm, p->comm, TASK_COMM_LEN)
write \0
The consequences depend on how 'other' uses the string. In our case,
it was copied into the tracing system's saved cmdlines, a buffer of
adjacent TASK_COMM_LEN-byte buffers (note the 'n' where 0 should be):
crash-arm64> x/1024s savedcmd->saved_cmdlines | grep 'evenk'
0xffffffd5b3818640: "irq/497-pwr_evenkworker/u16:12"
...and a strcpy out of there would cause stack corruption:
[224761.522292] Kernel panic - not syncing: stack-protector:
Kernel stack is corrupted in: ffffff9bf9783c78
crash-arm64> kbt | grep 'comm\|trace_print_context'
#6 0xffffff9bf9783c78 in trace_print_context+0x18c(+396)
comm (char [16]) = "irq/497-pwr_even"
crash-arm64> rd 0xffffffd4d0e17d14 8
ffffffd4d0e17d14: 2f71726900000000 5f7277702d373934 ....irq/497-pwr_
ffffffd4d0e17d24: 726f776b6e657665 3a3631752f72656b evenkworker/u16:
ffffffd4d0e17d34: f9780248ff003231 cede60e0ffffff9b 12..H.x......`..
ffffffd4d0e17d44: cede60c8ffffffd4 00000fffffffffd4 .....`..........
The workaround in e09e28671 (use strlcpy in __trace_find_cmdline) was
likely needed because of this same bug.
Solved by vsnprintf:ing to a local buffer, then using set_task_comm().
This way, there won't be a window where comm is not terminated.
Cc: stable(a)vger.kernel.org
Fixes: bc0c38d139ec7 ("ftrace: latency tracer infrastructure")
Reviewed-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
[backported to 3.18 / 4.4 by Snild]
Signed-off-by: Snild Dolkow <snild(a)sony.com>
---
kernel/kthread.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 850b255..ac6849e 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -313,10 +313,16 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
task = create->result;
if (!IS_ERR(task)) {
static const struct sched_param param = { .sched_priority = 0 };
+ char name[TASK_COMM_LEN];
va_list args;
va_start(args, namefmt);
- vsnprintf(task->comm, sizeof(task->comm), namefmt, args);
+ /*
+ * task is already visible to other tasks, so updating
+ * COMM must be protected.
+ */
+ vsnprintf(name, sizeof(name), namefmt, args);
+ set_task_comm(task, name);
va_end(args);
/*
* root may have changed our (kthreadd's) priority or CPU mask.
--
2.7.4
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 8a9dbb779fe882325b9a0238494a7afaff2eb444 Mon Sep 17 00:00:00 2001
From: Chanwoo Choi <cw00.choi(a)samsung.com>
Date: Thu, 14 Jun 2018 11:16:29 +0900
Subject: [PATCH] extcon: Release locking when sending the notification of
connector state
Previously, extcon used the spinlock before calling the notifier_call_chain
to prevent the scheduled out of task and to prevent the notification delay.
When spinlock is locked for sending the notification, deadlock issue
occured on the side of extcon consumer device. To fix this issue,
extcon consumer device should always use the work. it is always not
reasonable to use work.
To fix this issue on extcon consumer device, release locking when sending
the notification of connector state.
Fixes: ab11af049f88 ("extcon: Add the synchronization extcon APIs to support the notification")
Cc: stable(a)vger.kernel.org
Cc: Roger Quadros <rogerq(a)ti.com>
Cc: Kishon Vijay Abraham I <kishon(a)ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi(a)samsung.com>
diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
index af83ad58819c..b9d27c8fe57e 100644
--- a/drivers/extcon/extcon.c
+++ b/drivers/extcon/extcon.c
@@ -433,8 +433,8 @@ int extcon_sync(struct extcon_dev *edev, unsigned int id)
return index;
spin_lock_irqsave(&edev->lock, flags);
-
state = !!(edev->state & BIT(index));
+ spin_unlock_irqrestore(&edev->lock, flags);
/*
* Call functions in a raw notifier chain for the specific one
@@ -448,6 +448,7 @@ int extcon_sync(struct extcon_dev *edev, unsigned int id)
*/
raw_notifier_call_chain(&edev->nh_all, state, edev);
+ spin_lock_irqsave(&edev->lock, flags);
/* This could be in interrupt handler */
prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
if (!prop_buf) {
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 5b1fe7bec8a8d0cc547a22e7ddc2bd59acd67de4 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <idryomov(a)gmail.com>
Date: Thu, 9 Aug 2018 12:38:28 +0200
Subject: [PATCH] dm cache metadata: set dirty on all cache blocks after a
crash
Quoting Documentation/device-mapper/cache.txt:
The 'dirty' state for a cache block changes far too frequently for us
to keep updating it on the fly. So we treat it as a hint. In normal
operation it will be written when the dm device is suspended. If the
system crashes all cache blocks will be assumed dirty when restarted.
This got broken in commit f177940a8091 ("dm cache metadata: switch to
using the new cursor api for loading metadata") in 4.9, which removed
the code that consulted cmd->clean_when_opened (CLEAN_SHUTDOWN on-disk
flag) when loading cache blocks. This results in data corruption on an
unclean shutdown with dirty cache blocks on the fast device. After the
crash those blocks are considered clean and may get evicted from the
cache at any time. This can be demonstrated by doing a lot of reads
to trigger individual evictions, but uncache is more predictable:
### Disable auto-activation in lvm.conf to be able to do uncache in
### time (i.e. see uncache doing flushing) when the fix is applied.
# xfs_io -d -c 'pwrite -b 4M -S 0xaa 0 1G' /dev/vdb
# vgcreate vg_cache /dev/vdb /dev/vdc
# lvcreate -L 1G -n lv_slowdev vg_cache /dev/vdb
# lvcreate -L 512M -n lv_cachedev vg_cache /dev/vdc
# lvcreate -L 256M -n lv_metadev vg_cache /dev/vdc
# lvconvert --type cache-pool --cachemode writeback vg_cache/lv_cachedev --poolmetadata vg_cache/lv_metadev
# lvconvert --type cache vg_cache/lv_slowdev --cachepool vg_cache/lv_cachedev
# xfs_io -d -c 'pwrite -b 4M -S 0xbb 0 512M' /dev/mapper/vg_cache-lv_slowdev
# xfs_io -d -c 'pread -v 254M 512' /dev/mapper/vg_cache-lv_slowdev | head -n 2
0fe00000: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
0fe00010: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
# dmsetup status vg_cache-lv_slowdev
0 2097152 cache 8 27/65536 128 8192/8192 1 100 0 0 0 8192 7065 2 metadata2 writeback 2 migration_threshold 2048 smq 0 rw -
^^^^
7065 * 64k = 441M yet to be written to the slow device
# echo b >/proc/sysrq-trigger
# vgchange -ay vg_cache
# xfs_io -d -c 'pread -v 254M 512' /dev/mapper/vg_cache-lv_slowdev | head -n 2
0fe00000: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
0fe00010: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
# lvconvert --uncache vg_cache/lv_slowdev
Flushing 0 blocks for cache vg_cache/lv_slowdev.
Logical volume "lv_cachedev" successfully removed
Logical volume vg_cache/lv_slowdev is not cached.
# xfs_io -d -c 'pread -v 254M 512' /dev/mapper/vg_cache-lv_slowdev | head -n 2
0fe00000: aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa ................
0fe00010: aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa ................
This is the case with both v1 and v2 cache pool metatata formats.
After applying this patch:
# vgchange -ay vg_cache
# xfs_io -d -c 'pread -v 254M 512' /dev/mapper/vg_cache-lv_slowdev | head -n 2
0fe00000: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
0fe00010: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
# lvconvert --uncache vg_cache/lv_slowdev
Flushing 3724 blocks for cache vg_cache/lv_slowdev.
...
Flushing 71 blocks for cache vg_cache/lv_slowdev.
Logical volume "lv_cachedev" successfully removed
Logical volume vg_cache/lv_slowdev is not cached.
# xfs_io -d -c 'pread -v 254M 512' /dev/mapper/vg_cache-lv_slowdev | head -n 2
0fe00000: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
0fe00010: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
Cc: stable(a)vger.kernel.org
Fixes: f177940a8091 ("dm cache metadata: switch to using the new cursor api for loading metadata")
Signed-off-by: Ilya Dryomov <idryomov(a)gmail.com>
Signed-off-by: Mike Snitzer <snitzer(a)redhat.com>
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index 1a449105b007..69dddeab124c 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -1323,6 +1323,7 @@ static int __load_mapping_v1(struct dm_cache_metadata *cmd,
dm_oblock_t oblock;
unsigned flags;
+ bool dirty = true;
dm_array_cursor_get_value(mapping_cursor, (void **) &mapping_value_le);
memcpy(&mapping, mapping_value_le, sizeof(mapping));
@@ -1333,8 +1334,10 @@ static int __load_mapping_v1(struct dm_cache_metadata *cmd,
dm_array_cursor_get_value(hint_cursor, (void **) &hint_value_le);
memcpy(&hint, hint_value_le, sizeof(hint));
}
+ if (cmd->clean_when_opened)
+ dirty = flags & M_DIRTY;
- r = fn(context, oblock, to_cblock(cb), flags & M_DIRTY,
+ r = fn(context, oblock, to_cblock(cb), dirty,
le32_to_cpu(hint), hints_valid);
if (r) {
DMERR("policy couldn't load cache block %llu",
@@ -1362,7 +1365,7 @@ static int __load_mapping_v2(struct dm_cache_metadata *cmd,
dm_oblock_t oblock;
unsigned flags;
- bool dirty;
+ bool dirty = true;
dm_array_cursor_get_value(mapping_cursor, (void **) &mapping_value_le);
memcpy(&mapping, mapping_value_le, sizeof(mapping));
@@ -1373,8 +1376,9 @@ static int __load_mapping_v2(struct dm_cache_metadata *cmd,
dm_array_cursor_get_value(hint_cursor, (void **) &hint_value_le);
memcpy(&hint, hint_value_le, sizeof(hint));
}
+ if (cmd->clean_when_opened)
+ dirty = dm_bitset_cursor_get_value(dirty_cursor);
- dirty = dm_bitset_cursor_get_value(dirty_cursor);
r = fn(context, oblock, to_cblock(cb), dirty,
le32_to_cpu(hint), hints_valid);
if (r) {
The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 75294442d896f2767be34f75aca7cc2b0d01301f Mon Sep 17 00:00:00 2001
From: Hou Tao <houtao1(a)huawei.com>
Date: Thu, 2 Aug 2018 16:18:24 +0800
Subject: [PATCH] dm thin: stop no_space_timeout worker when switching to
write-mode
Now both check_for_space() and do_no_space_timeout() will read & write
pool->pf.error_if_no_space. If these functions run concurrently, as
shown in the following case, the default setting of "queue_if_no_space"
can get lost.
precondition:
* error_if_no_space = false (aka "queue_if_no_space")
* pool is in Out-of-Data-Space (OODS) mode
* no_space_timeout worker has been queued
CPU 0: CPU 1:
// delete a thin device
process_delete_mesg()
// check_for_space() invoked by commit()
set_pool_mode(pool, PM_WRITE)
pool->pf.error_if_no_space = \
pt->requested_pf.error_if_no_space
// timeout, pool is still in OODS mode
do_no_space_timeout
// "queue_if_no_space" config is lost
pool->pf.error_if_no_space = true
pool->pf.mode = new_mode
Fix it by stopping no_space_timeout worker when switching to write mode.
Fixes: bcc696fac11f ("dm thin: stay in out-of-data-space mode once no_space_timeout expires")
Cc: stable(a)vger.kernel.org
Signed-off-by: Hou Tao <houtao1(a)huawei.com>
Signed-off-by: Mike Snitzer <snitzer(a)redhat.com>
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 5997d6808b57..7bd60a150f8f 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -2503,6 +2503,8 @@ static void set_pool_mode(struct pool *pool, enum pool_mode new_mode)
case PM_WRITE:
if (old_mode != new_mode)
notify_of_pool_mode_change(pool, "write");
+ if (old_mode == PM_OUT_OF_DATA_SPACE)
+ cancel_delayed_work_sync(&pool->no_space_timeout);
pool->out_of_data_space = false;
pool->pf.error_if_no_space = pt->requested_pf.error_if_no_space;
dm_pool_metadata_read_write(pool->pmd);
The patch below does not apply to the 4.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 05f58ceba123bdb420cf44c6ea04b6db467edd1c Mon Sep 17 00:00:00 2001
From: Leon Romanovsky <leonro(a)mellanox.com>
Date: Sun, 8 Jul 2018 13:50:21 +0300
Subject: [PATCH] RDMA/mlx5: Check that supplied blue flame index doesn't
overflow
User's supplied index is checked again total number of system pages, but
this number already includes num_static_sys_pages, so addition of that
value to supplied index causes to below error while trying to access
sys_pages[].
BUG: KASAN: slab-out-of-bounds in bfregn_to_uar_index+0x34f/0x400
Read of size 4 at addr ffff880065561904 by task syz-executor446/314
CPU: 0 PID: 314 Comm: syz-executor446 Not tainted 4.18.0-rc1+ #256
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
Call Trace:
dump_stack+0xef/0x17e
print_address_description+0x83/0x3b0
kasan_report+0x18d/0x4d0
bfregn_to_uar_index+0x34f/0x400
create_user_qp+0x272/0x227d
create_qp_common+0x32eb/0x43e0
mlx5_ib_create_qp+0x379/0x1ca0
create_qp.isra.5+0xc94/0x22d0
ib_uverbs_create_qp+0x21b/0x2a0
ib_uverbs_write+0xc2c/0x1010
vfs_write+0x1b0/0x550
ksys_write+0xc6/0x1a0
do_syscall_64+0xa7/0x590
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x433679
Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 91 fd ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff2b3d8e48 EFLAGS: 00000217 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00000000004002f8 RCX: 0000000000433679
RDX: 0000000000000040 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 00000000006d4018 R08: 00000000004002f8 R09: 00000000004002f8
R10: 00000000004002f8 R11: 0000000000000217 R12: 0000000000000000
R13: 000000000040cb00 R14: 000000000040cb90 R15: 0000000000000006
Allocated by task 314:
kasan_kmalloc+0xa0/0xd0
__kmalloc+0x1a9/0x510
mlx5_ib_alloc_ucontext+0x966/0x2620
ib_uverbs_get_context+0x23f/0xa60
ib_uverbs_write+0xc2c/0x1010
__vfs_write+0x10d/0x720
vfs_write+0x1b0/0x550
ksys_write+0xc6/0x1a0
do_syscall_64+0xa7/0x590
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 1:
__kasan_slab_free+0x12e/0x180
kfree+0x159/0x630
kvfree+0x37/0x50
single_release+0x8e/0xf0
__fput+0x2d8/0x900
task_work_run+0x102/0x1f0
exit_to_usermode_loop+0x159/0x1c0
do_syscall_64+0x408/0x590
entry_SYSCALL_64_after_hwframe+0x49/0xbe
The buggy address belongs to the object at ffff880065561100
which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 2052 bytes inside of
4096-byte region [ffff880065561100, ffff880065562100)
The buggy address belongs to the page:
page:ffffea0001955800 count:1 mapcount:0 mapping:ffff88006c402480 index:0x0 compound_mapcount: 0
flags: 0x4000000000008100(slab|head)
raw: 4000000000008100 ffffea0001a7c000 0000000200000002 ffff88006c402480
raw: 0000000000000000 0000000080070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff880065561800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff880065561880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff880065561900: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff880065561980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff880065561a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
Cc: <stable(a)vger.kernel.org> # 4.15
Fixes: 1ee47ab3e8d8 ("IB/mlx5: Enable QP creation with a given blue flame index")
Reported-by: Noa Osherovich <noaos(a)mellanox.com>
Signed-off-by: Leon Romanovsky <leonro(a)mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg(a)mellanox.com>
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 93087409f4b8..04a5d82c9cf3 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -1330,6 +1330,6 @@ unsigned long mlx5_ib_get_xlt_emergency_page(void);
void mlx5_ib_put_xlt_emergency_page(void);
int bfregn_to_uar_index(struct mlx5_ib_dev *dev,
- struct mlx5_bfreg_info *bfregi, int bfregn,
+ struct mlx5_bfreg_info *bfregi, u32 bfregn,
bool dyn_bfreg);
#endif /* MLX5_IB_H */
diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 51e68ca20215..d4414015b64f 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -631,22 +631,23 @@ static void mlx5_ib_unlock_cqs(struct mlx5_ib_cq *send_cq,
struct mlx5_ib_cq *recv_cq);
int bfregn_to_uar_index(struct mlx5_ib_dev *dev,
- struct mlx5_bfreg_info *bfregi, int bfregn,
+ struct mlx5_bfreg_info *bfregi, u32 bfregn,
bool dyn_bfreg)
{
- int bfregs_per_sys_page;
- int index_of_sys_page;
- int offset;
+ unsigned int bfregs_per_sys_page;
+ u32 index_of_sys_page;
+ u32 offset;
bfregs_per_sys_page = get_uars_per_sys_page(dev, bfregi->lib_uar_4k) *
MLX5_NON_FP_BFREGS_PER_UAR;
index_of_sys_page = bfregn / bfregs_per_sys_page;
- if (index_of_sys_page >= bfregi->num_sys_pages)
- return -EINVAL;
-
if (dyn_bfreg) {
index_of_sys_page += bfregi->num_static_sys_pages;
+
+ if (index_of_sys_page >= bfregi->num_sys_pages)
+ return -EINVAL;
+
if (bfregn > bfregi->num_dyn_bfregs ||
bfregi->sys_pages[index_of_sys_page] == MLX5_IB_INVALID_UAR_INDEX) {
mlx5_ib_dbg(dev, "Invalid dynamic uar index\n");
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 94675cceacaec27a30eefb142c4c59a9d3131742 Mon Sep 17 00:00:00 2001
From: Mahesh Salgaonkar <mahesh(a)linux.vnet.ibm.com>
Date: Wed, 4 Jul 2018 23:27:21 +0530
Subject: [PATCH] powerpc/pseries: Defer the logging of rtas error to irq work
queue.
rtas_log_buf is a buffer to hold RTAS event data that are communicated
to kernel by hypervisor. This buffer is then used to pass RTAS event
data to user through proc fs. This buffer is allocated from
vmalloc (non-linear mapping) area.
On Machine check interrupt, register r3 points to RTAS extended event
log passed by hypervisor that contains the MCE event. The pseries
machine check handler then logs this error into rtas_log_buf. The
rtas_log_buf is a vmalloc-ed (non-linear) buffer we end up taking up a
page fault (vector 0x300) while accessing it. Since machine check
interrupt handler runs in NMI context we can not afford to take any
page fault. Page faults are not honored in NMI context and causes
kernel panic. Apart from that, as Nick pointed out,
pSeries_log_error() also takes a spin_lock while logging error which
is not safe in NMI context. It may endup in deadlock if we get another
MCE before releasing the lock. Fix this by deferring the logging of
rtas error to irq work queue.
Current implementation uses two different buffers to hold rtas error
log depending on whether extended log is provided or not. This makes
bit difficult to identify which buffer has valid data that needs to
logged later in irq work. Simplify this using single buffer, one per
paca, and copy rtas log to it irrespective of whether extended log is
provided or not. Allocate this buffer below RMA region so that it can
be accessed in real mode mce handler.
Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt")
Cc: stable(a)vger.kernel.org # v4.14+
Reviewed-by: Nicholas Piggin <npiggin(a)gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh(a)linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 4e9cede5a7e7..ad4f16164619 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -247,6 +247,9 @@ struct paca_struct {
void *rfi_flush_fallback_area;
u64 l1d_flush_size;
#endif
+#ifdef CONFIG_PPC_PSERIES
+ u8 *mce_data_buf; /* buffer to hold per cpu rtas errlog */
+#endif /* CONFIG_PPC_PSERIES */
} ____cacheline_aligned;
extern void copy_mm_to_paca(struct mm_struct *mm);
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index ef104144d4bc..14a46b07ab2f 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -22,6 +22,7 @@
#include <linux/of.h>
#include <linux/fs.h>
#include <linux/reboot.h>
+#include <linux/irq_work.h>
#include <asm/machdep.h>
#include <asm/rtas.h>
@@ -32,11 +33,13 @@
static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
static DEFINE_SPINLOCK(ras_log_buf_lock);
-static char global_mce_data_buf[RTAS_ERROR_LOG_MAX];
-static DEFINE_PER_CPU(__u64, mce_data_buf);
-
static int ras_check_exception_token;
+static void mce_process_errlog_event(struct irq_work *work);
+static struct irq_work mce_errlog_process_work = {
+ .func = mce_process_errlog_event,
+};
+
#define EPOW_SENSOR_TOKEN 9
#define EPOW_SENSOR_INDEX 0
@@ -330,16 +333,20 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
((((A) >= 0x7000) && ((A) < 0x7ff0)) || \
(((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16))))
+static inline struct rtas_error_log *fwnmi_get_errlog(void)
+{
+ return (struct rtas_error_log *)local_paca->mce_data_buf;
+}
+
/*
* Get the error information for errors coming through the
* FWNMI vectors. The pt_regs' r3 will be updated to reflect
* the actual r3 if possible, and a ptr to the error log entry
* will be returned if found.
*
- * If the RTAS error is not of the extended type, then we put it in a per
- * cpu 64bit buffer. If it is the extended type we use global_mce_data_buf.
+ * Use one buffer mce_data_buf per cpu to store RTAS error.
*
- * The global_mce_data_buf does not have any locks or protection around it,
+ * The mce_data_buf does not have any locks or protection around it,
* if a second machine check comes in, or a system reset is done
* before we have logged the error, then we will get corruption in the
* error log. This is preferable over holding off on calling
@@ -349,7 +356,7 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
{
unsigned long *savep;
- struct rtas_error_log *h, *errhdr = NULL;
+ struct rtas_error_log *h;
/* Mask top two bits */
regs->gpr[3] &= ~(0x3UL << 62);
@@ -362,22 +369,20 @@ static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
savep = __va(regs->gpr[3]);
regs->gpr[3] = savep[0]; /* restore original r3 */
- /* If it isn't an extended log we can use the per cpu 64bit buffer */
h = (struct rtas_error_log *)&savep[1];
+ /* Use the per cpu buffer from paca to store rtas error log */
+ memset(local_paca->mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
if (!rtas_error_extended(h)) {
- memcpy(this_cpu_ptr(&mce_data_buf), h, sizeof(__u64));
- errhdr = (struct rtas_error_log *)this_cpu_ptr(&mce_data_buf);
+ memcpy(local_paca->mce_data_buf, h, sizeof(__u64));
} else {
int len, error_log_length;
error_log_length = 8 + rtas_error_extended_log_length(h);
len = min_t(int, error_log_length, RTAS_ERROR_LOG_MAX);
- memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
- memcpy(global_mce_data_buf, h, len);
- errhdr = (struct rtas_error_log *)global_mce_data_buf;
+ memcpy(local_paca->mce_data_buf, h, len);
}
- return errhdr;
+ return (struct rtas_error_log *)local_paca->mce_data_buf;
}
/* Call this when done with the data returned by FWNMI_get_errinfo.
@@ -422,6 +427,17 @@ int pSeries_system_reset_exception(struct pt_regs *regs)
return 0; /* need to perform reset */
}
+/*
+ * Process MCE rtas errlog event.
+ */
+static void mce_process_errlog_event(struct irq_work *work)
+{
+ struct rtas_error_log *err;
+
+ err = fwnmi_get_errlog();
+ log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
+}
+
/*
* See if we can recover from a machine check exception.
* This is only called on power4 (or above) and only via
@@ -466,7 +482,8 @@ static int recover_mce(struct pt_regs *regs, struct rtas_error_log *err)
recovered = 1;
}
- log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
+ /* Queue irq work to log this rtas event later. */
+ irq_work_queue(&mce_errlog_process_work);
return recovered;
}
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 9948ad16f788..b411a74b861d 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -41,6 +41,7 @@
#include <linux/root_dev.h>
#include <linux/of.h>
#include <linux/of_pci.h>
+#include <linux/memblock.h>
#include <asm/mmu.h>
#include <asm/processor.h>
@@ -102,6 +103,9 @@ static void pSeries_show_cpuinfo(struct seq_file *m)
static void __init fwnmi_init(void)
{
unsigned long system_reset_addr, machine_check_addr;
+ u8 *mce_data_buf;
+ unsigned int i;
+ int nr_cpus = num_possible_cpus();
int ibm_nmi_register = rtas_token("ibm,nmi-register");
if (ibm_nmi_register == RTAS_UNKNOWN_SERVICE)
@@ -115,6 +119,18 @@ static void __init fwnmi_init(void)
if (0 == rtas_call(ibm_nmi_register, 2, 1, NULL, system_reset_addr,
machine_check_addr))
fwnmi_active = 1;
+
+ /*
+ * Allocate a chunk for per cpu buffer to hold rtas errorlog.
+ * It will be used in real mode mce handler, hence it needs to be
+ * below RMA.
+ */
+ mce_data_buf = __va(memblock_alloc_base(RTAS_ERROR_LOG_MAX * nr_cpus,
+ RTAS_ERROR_LOG_MAX, ppc64_rma_size));
+ for_each_possible_cpu(i) {
+ paca_ptrs[i]->mce_data_buf = mce_data_buf +
+ (RTAS_ERROR_LOG_MAX * i);
+ }
}
static void pseries_8259_cascade(struct irq_desc *desc)
The patch below does not apply to the 4.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 94675cceacaec27a30eefb142c4c59a9d3131742 Mon Sep 17 00:00:00 2001
From: Mahesh Salgaonkar <mahesh(a)linux.vnet.ibm.com>
Date: Wed, 4 Jul 2018 23:27:21 +0530
Subject: [PATCH] powerpc/pseries: Defer the logging of rtas error to irq work
queue.
rtas_log_buf is a buffer to hold RTAS event data that are communicated
to kernel by hypervisor. This buffer is then used to pass RTAS event
data to user through proc fs. This buffer is allocated from
vmalloc (non-linear mapping) area.
On Machine check interrupt, register r3 points to RTAS extended event
log passed by hypervisor that contains the MCE event. The pseries
machine check handler then logs this error into rtas_log_buf. The
rtas_log_buf is a vmalloc-ed (non-linear) buffer we end up taking up a
page fault (vector 0x300) while accessing it. Since machine check
interrupt handler runs in NMI context we can not afford to take any
page fault. Page faults are not honored in NMI context and causes
kernel panic. Apart from that, as Nick pointed out,
pSeries_log_error() also takes a spin_lock while logging error which
is not safe in NMI context. It may endup in deadlock if we get another
MCE before releasing the lock. Fix this by deferring the logging of
rtas error to irq work queue.
Current implementation uses two different buffers to hold rtas error
log depending on whether extended log is provided or not. This makes
bit difficult to identify which buffer has valid data that needs to
logged later in irq work. Simplify this using single buffer, one per
paca, and copy rtas log to it irrespective of whether extended log is
provided or not. Allocate this buffer below RMA region so that it can
be accessed in real mode mce handler.
Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt")
Cc: stable(a)vger.kernel.org # v4.14+
Reviewed-by: Nicholas Piggin <npiggin(a)gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh(a)linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 4e9cede5a7e7..ad4f16164619 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -247,6 +247,9 @@ struct paca_struct {
void *rfi_flush_fallback_area;
u64 l1d_flush_size;
#endif
+#ifdef CONFIG_PPC_PSERIES
+ u8 *mce_data_buf; /* buffer to hold per cpu rtas errlog */
+#endif /* CONFIG_PPC_PSERIES */
} ____cacheline_aligned;
extern void copy_mm_to_paca(struct mm_struct *mm);
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index ef104144d4bc..14a46b07ab2f 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -22,6 +22,7 @@
#include <linux/of.h>
#include <linux/fs.h>
#include <linux/reboot.h>
+#include <linux/irq_work.h>
#include <asm/machdep.h>
#include <asm/rtas.h>
@@ -32,11 +33,13 @@
static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
static DEFINE_SPINLOCK(ras_log_buf_lock);
-static char global_mce_data_buf[RTAS_ERROR_LOG_MAX];
-static DEFINE_PER_CPU(__u64, mce_data_buf);
-
static int ras_check_exception_token;
+static void mce_process_errlog_event(struct irq_work *work);
+static struct irq_work mce_errlog_process_work = {
+ .func = mce_process_errlog_event,
+};
+
#define EPOW_SENSOR_TOKEN 9
#define EPOW_SENSOR_INDEX 0
@@ -330,16 +333,20 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
((((A) >= 0x7000) && ((A) < 0x7ff0)) || \
(((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16))))
+static inline struct rtas_error_log *fwnmi_get_errlog(void)
+{
+ return (struct rtas_error_log *)local_paca->mce_data_buf;
+}
+
/*
* Get the error information for errors coming through the
* FWNMI vectors. The pt_regs' r3 will be updated to reflect
* the actual r3 if possible, and a ptr to the error log entry
* will be returned if found.
*
- * If the RTAS error is not of the extended type, then we put it in a per
- * cpu 64bit buffer. If it is the extended type we use global_mce_data_buf.
+ * Use one buffer mce_data_buf per cpu to store RTAS error.
*
- * The global_mce_data_buf does not have any locks or protection around it,
+ * The mce_data_buf does not have any locks or protection around it,
* if a second machine check comes in, or a system reset is done
* before we have logged the error, then we will get corruption in the
* error log. This is preferable over holding off on calling
@@ -349,7 +356,7 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
{
unsigned long *savep;
- struct rtas_error_log *h, *errhdr = NULL;
+ struct rtas_error_log *h;
/* Mask top two bits */
regs->gpr[3] &= ~(0x3UL << 62);
@@ -362,22 +369,20 @@ static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
savep = __va(regs->gpr[3]);
regs->gpr[3] = savep[0]; /* restore original r3 */
- /* If it isn't an extended log we can use the per cpu 64bit buffer */
h = (struct rtas_error_log *)&savep[1];
+ /* Use the per cpu buffer from paca to store rtas error log */
+ memset(local_paca->mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
if (!rtas_error_extended(h)) {
- memcpy(this_cpu_ptr(&mce_data_buf), h, sizeof(__u64));
- errhdr = (struct rtas_error_log *)this_cpu_ptr(&mce_data_buf);
+ memcpy(local_paca->mce_data_buf, h, sizeof(__u64));
} else {
int len, error_log_length;
error_log_length = 8 + rtas_error_extended_log_length(h);
len = min_t(int, error_log_length, RTAS_ERROR_LOG_MAX);
- memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
- memcpy(global_mce_data_buf, h, len);
- errhdr = (struct rtas_error_log *)global_mce_data_buf;
+ memcpy(local_paca->mce_data_buf, h, len);
}
- return errhdr;
+ return (struct rtas_error_log *)local_paca->mce_data_buf;
}
/* Call this when done with the data returned by FWNMI_get_errinfo.
@@ -422,6 +427,17 @@ int pSeries_system_reset_exception(struct pt_regs *regs)
return 0; /* need to perform reset */
}
+/*
+ * Process MCE rtas errlog event.
+ */
+static void mce_process_errlog_event(struct irq_work *work)
+{
+ struct rtas_error_log *err;
+
+ err = fwnmi_get_errlog();
+ log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
+}
+
/*
* See if we can recover from a machine check exception.
* This is only called on power4 (or above) and only via
@@ -466,7 +482,8 @@ static int recover_mce(struct pt_regs *regs, struct rtas_error_log *err)
recovered = 1;
}
- log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
+ /* Queue irq work to log this rtas event later. */
+ irq_work_queue(&mce_errlog_process_work);
return recovered;
}
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 9948ad16f788..b411a74b861d 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -41,6 +41,7 @@
#include <linux/root_dev.h>
#include <linux/of.h>
#include <linux/of_pci.h>
+#include <linux/memblock.h>
#include <asm/mmu.h>
#include <asm/processor.h>
@@ -102,6 +103,9 @@ static void pSeries_show_cpuinfo(struct seq_file *m)
static void __init fwnmi_init(void)
{
unsigned long system_reset_addr, machine_check_addr;
+ u8 *mce_data_buf;
+ unsigned int i;
+ int nr_cpus = num_possible_cpus();
int ibm_nmi_register = rtas_token("ibm,nmi-register");
if (ibm_nmi_register == RTAS_UNKNOWN_SERVICE)
@@ -115,6 +119,18 @@ static void __init fwnmi_init(void)
if (0 == rtas_call(ibm_nmi_register, 2, 1, NULL, system_reset_addr,
machine_check_addr))
fwnmi_active = 1;
+
+ /*
+ * Allocate a chunk for per cpu buffer to hold rtas errorlog.
+ * It will be used in real mode mce handler, hence it needs to be
+ * below RMA.
+ */
+ mce_data_buf = __va(memblock_alloc_base(RTAS_ERROR_LOG_MAX * nr_cpus,
+ RTAS_ERROR_LOG_MAX, ppc64_rma_size));
+ for_each_possible_cpu(i) {
+ paca_ptrs[i]->mce_data_buf = mce_data_buf +
+ (RTAS_ERROR_LOG_MAX * i);
+ }
}
static void pseries_8259_cascade(struct irq_desc *desc)