<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers, branch v5.1.4</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>libnvdimm/namespace: Fix label tracking error</title>
<updated>2019-05-22T05:39:58+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2019-05-01T04:51:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=550f5ba19cbd9217cb4d9dfc0e3ff37aeb1d4274'/>
<id>550f5ba19cbd9217cb4d9dfc0e3ff37aeb1d4274</id>
<content type='text'>
commit c4703ce11c23423d4b46e3d59aef7979814fd608 upstream.

Users have reported intermittent occurrences of DIMM initialization
failures due to duplicate allocations of address capacity detected in
the labels, or errors of the form below, both have the same root cause.

    nd namespace1.4: failed to track label: 0
    WARNING: CPU: 17 PID: 1381 at drivers/nvdimm/label.c:863

    RIP: 0010:__pmem_label_update+0x56c/0x590 [libnvdimm]
    Call Trace:
     ? nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     uuid_store+0x17e/0x190 [libnvdimm]
     kernfs_fop_write+0xf0/0x1a0
     vfs_write+0xb7/0x1b0
     ksys_write+0x57/0xd0
     do_syscall_64+0x60/0x210

Unfortunately those reports were typically with a busy parallel
namespace creation / destruction loop making it difficult to see the
components of the bug. However, Jane provided a simple reproducer using
the work-in-progress sub-section implementation.

When ndctl is reconfiguring a namespace it may take an existing defunct
/ disabled namespace and reconfigure it with a new uuid and other
parameters. Critically namespace_update_uuid() takes existing address
resources and renames them for the new namespace to use / reconfigure as
it sees fit. The bug is that this rename only happens in the resource
tracking tree. Existing labels with the old uuid are not reaped leading
to a scenario where multiple active labels reference the same span of
address range.

Teach namespace_update_uuid() to flag any references to the old uuid for
reaping at the next label update attempt.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation")
Link: https://github.com/pmem/ndctl/issues/91
Reported-by: Jane Chu &lt;jane.chu@oracle.com&gt;
Reported-by: Jeff Moyer &lt;jmoyer@redhat.com&gt;
Reported-by: Erwin Tsaur &lt;erwin.tsaur@oracle.com&gt;
Cc: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c4703ce11c23423d4b46e3d59aef7979814fd608 upstream.

Users have reported intermittent occurrences of DIMM initialization
failures due to duplicate allocations of address capacity detected in
the labels, or errors of the form below, both have the same root cause.

    nd namespace1.4: failed to track label: 0
    WARNING: CPU: 17 PID: 1381 at drivers/nvdimm/label.c:863

    RIP: 0010:__pmem_label_update+0x56c/0x590 [libnvdimm]
    Call Trace:
     ? nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     uuid_store+0x17e/0x190 [libnvdimm]
     kernfs_fop_write+0xf0/0x1a0
     vfs_write+0xb7/0x1b0
     ksys_write+0x57/0xd0
     do_syscall_64+0x60/0x210

Unfortunately those reports were typically with a busy parallel
namespace creation / destruction loop making it difficult to see the
components of the bug. However, Jane provided a simple reproducer using
the work-in-progress sub-section implementation.

When ndctl is reconfiguring a namespace it may take an existing defunct
/ disabled namespace and reconfigure it with a new uuid and other
parameters. Critically namespace_update_uuid() takes existing address
resources and renames them for the new namespace to use / reconfigure as
it sees fit. The bug is that this rename only happens in the resource
tracking tree. Existing labels with the old uuid are not reaped leading
to a scenario where multiple active labels reference the same span of
address range.

Teach namespace_update_uuid() to flag any references to the old uuid for
reaping at the next label update attempt.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation")
Link: https://github.com/pmem/ndctl/issues/91
Reported-by: Jane Chu &lt;jane.chu@oracle.com&gt;
Reported-by: Jeff Moyer &lt;jmoyer@redhat.com&gt;
Reported-by: Erwin Tsaur &lt;erwin.tsaur@oracle.com&gt;
Cc: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>tty: Don't force RISCV SBI console as preferred console</title>
<updated>2019-05-22T05:39:55+00:00</updated>
<author>
<name>Anup Patel</name>
<email>Anup.Patel@wdc.com</email>
</author>
<published>2019-04-25T13:35:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9e897e34419f9f76b07f6c3ed372ffed805c7e49'/>
<id>9e897e34419f9f76b07f6c3ed372ffed805c7e49</id>
<content type='text'>
commit f91253a3d005796404ae0e578b3394459b5f9b71 upstream.

The Linux kernel will auto-disables all boot consoles whenever it
gets a preferred real console.

Currently on RISC-V systems, if we have a real console which is not
RISCV SBI console then boot consoles (such as earlycon=sbi) are not
auto-disabled when a real console (ttyS0 or ttySIF0) is available.
This results in duplicate prints at boot-time after kernel starts
using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel
parameter was passed by bootloader.

The reason for above issue is that RISCV SBI console always adds
itself as preferred console which is causing other real consoles
to be not used as preferred console.

Ideally "console=" kernel parameter passed by bootloaders should
be the one selecting a preferred real console.

This patch fixes above issue by not forcing RISCV SBI console as
preferred console.

Fixes: afa6b1ccfad5 ("tty: New RISC-V SBI console driver")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel &lt;anup.patel@wdc.com&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f91253a3d005796404ae0e578b3394459b5f9b71 upstream.

The Linux kernel will auto-disables all boot consoles whenever it
gets a preferred real console.

Currently on RISC-V systems, if we have a real console which is not
RISCV SBI console then boot consoles (such as earlycon=sbi) are not
auto-disabled when a real console (ttyS0 or ttySIF0) is available.
This results in duplicate prints at boot-time after kernel starts
using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel
parameter was passed by bootloader.

The reason for above issue is that RISCV SBI console always adds
itself as preferred console which is causing other real consoles
to be not used as preferred console.

Ideally "console=" kernel parameter passed by bootloaders should
be the one selecting a preferred real console.

This patch fixes above issue by not forcing RISCV SBI console as
preferred console.

Fixes: afa6b1ccfad5 ("tty: New RISC-V SBI console driver")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel &lt;anup.patel@wdc.com&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ipmi:ssif: compare block number correctly for multi-part return messages</title>
<updated>2019-05-22T05:39:55+00:00</updated>
<author>
<name>Kamlakant Patel</name>
<email>kamlakantp@marvell.com</email>
</author>
<published>2019-04-24T11:50:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=14c7aae72d8ecd0989b39ac51a1b9335a9b44571'/>
<id>14c7aae72d8ecd0989b39ac51a1b9335a9b44571</id>
<content type='text'>
commit 55be8658c7e2feb11a5b5b33ee031791dbd23a69 upstream.

According to ipmi spec, block number is a number that is incremented,
starting with 0, for each new block of message data returned using the
middle transaction.

Here, the 'blocknum' is data[0] which always starts from zero(0) and
'ssif_info-&gt;multi_pos' starts from 1.
So, we need to add +1 to blocknum while comparing with multi_pos.

Fixes: 7d6380cd40f79 ("ipmi:ssif: Fix handling of multi-part return messages").
Reported-by: Kiran Kolukuluru &lt;kirank@ami.com&gt;
Signed-off-by: Kamlakant Patel &lt;kamlakantp@marvell.com&gt;
Message-Id: &lt;1556106615-18722-1-git-send-email-kamlakantp@marvell.com&gt;
[Also added a debug log if the block numbers don't match.]
Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&gt;
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 55be8658c7e2feb11a5b5b33ee031791dbd23a69 upstream.

According to ipmi spec, block number is a number that is incremented,
starting with 0, for each new block of message data returned using the
middle transaction.

Here, the 'blocknum' is data[0] which always starts from zero(0) and
'ssif_info-&gt;multi_pos' starts from 1.
So, we need to add +1 to blocknum while comparing with multi_pos.

Fixes: 7d6380cd40f79 ("ipmi:ssif: Fix handling of multi-part return messages").
Reported-by: Kiran Kolukuluru &lt;kirank@ami.com&gt;
Signed-off-by: Kamlakant Patel &lt;kamlakantp@marvell.com&gt;
Message-Id: &lt;1556106615-18722-1-git-send-email-kamlakantp@marvell.com&gt;
[Also added a debug log if the block numbers don't match.]
Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&gt;
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ipmi: Add the i2c-addr property for SSIF interfaces</title>
<updated>2019-05-22T05:39:55+00:00</updated>
<author>
<name>Corey Minyard</name>
<email>cminyard@mvista.com</email>
</author>
<published>2019-04-24T13:32:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ebad3ccb8ab688c80f792ab3c637de5c99fb35ab'/>
<id>ebad3ccb8ab688c80f792ab3c637de5c99fb35ab</id>
<content type='text'>
commit d73236383eb1cd4b7b65c33a09f0ed45f6781f40 upstream.

This is required for SSIF to work.

There was no way to know if the interface being added was SI
or SSIF from the platform data, but that was required so the
i2c-addr is only added for SSIF interfaces.  So add a field
for that.

Also rework the logic a bit so that ipmi-type is not set
for SSIF interfaces, as it is not necessary for that.

Fixes: 3cd83bac481d ("ipmi: Consolidate the adding of platform devices")
Reported-by: Kamlakant Patel &lt;kamlakantp@marvell.com&gt;
Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&gt;
Cc: stable@vger.kernel.org # 5.1
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d73236383eb1cd4b7b65c33a09f0ed45f6781f40 upstream.

This is required for SSIF to work.

There was no way to know if the interface being added was SI
or SSIF from the platform data, but that was required so the
i2c-addr is only added for SSIF interfaces.  So add a field
for that.

Also rework the logic a bit so that ipmi-type is not set
for SSIF interfaces, as it is not necessary for that.

Fixes: 3cd83bac481d ("ipmi: Consolidate the adding of platform devices")
Reported-by: Kamlakant Patel &lt;kamlakantp@marvell.com&gt;
Signed-off-by: Corey Minyard &lt;cminyard@mvista.com&gt;
Cc: stable@vger.kernel.org # 5.1
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: never set KEY_PTRS of journal key to 0 in journal_reclaim()</title>
<updated>2019-05-22T05:39:55+00:00</updated>
<author>
<name>Coly Li</name>
<email>colyli@suse.de</email>
</author>
<published>2019-04-24T16:48:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9c52c4cf74055872fdd4b3c98fa777a02e7a6558'/>
<id>9c52c4cf74055872fdd4b3c98fa777a02e7a6558</id>
<content type='text'>
commit 1bee2addc0c8470c8aaa65ef0599eeae96dd88bc upstream.

In journal_reclaim() ja-&gt;cur_idx of each cache will be update to
reclaim available journal buckets. Variable 'int n' is used to count how
many cache is successfully reclaimed, then n is set to c-&gt;journal.key
by SET_KEY_PTRS(). Later in journal_write_unlocked(), a for_each_cache()
loop will write the jset data onto each cache.

The problem is, if all jouranl buckets on each cache is full, the
following code in journal_reclaim(),

529 for_each_cache(ca, c, iter) {
530       struct journal_device *ja = &amp;ca-&gt;journal;
531       unsigned int next = (ja-&gt;cur_idx + 1) % ca-&gt;sb.njournal_buckets;
532
533       /* No space available on this device */
534       if (next == ja-&gt;discard_idx)
535               continue;
536
537       ja-&gt;cur_idx = next;
538       k-&gt;ptr[n++] = MAKE_PTR(0,
539                         bucket_to_sector(c, ca-&gt;sb.d[ja-&gt;cur_idx]),
540                         ca-&gt;sb.nr_this_dev);
541 }
542
543 bkey_init(k);
544 SET_KEY_PTRS(k, n);

If there is no available bucket to reclaim, the if() condition at line
534 will always true, and n remains 0. Then at line 544, SET_KEY_PTRS()
will set KEY_PTRS field of c-&gt;journal.key to 0.

Setting KEY_PTRS field of c-&gt;journal.key to 0 is wrong. Because in
journal_write_unlocked() the journal data is written in following loop,

649	for (i = 0; i &lt; KEY_PTRS(k); i++) {
650-671		submit journal data to cache device
672	}

If KEY_PTRS field is set to 0 in jouranl_reclaim(), the journal data
won't be written to cache device here. If system crahed or rebooted
before bkeys of the lost journal entries written into btree nodes, data
corruption will be reported during bcache reload after rebooting the
system.

Indeed there is only one cache in a cache set, there is no need to set
KEY_PTRS field in journal_reclaim() at all. But in order to keep the
for_each_cache() logic consistent for now, this patch fixes the above
problem by not setting 0 KEY_PTRS of journal key, if there is no bucket
available to reclaim.

Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1bee2addc0c8470c8aaa65ef0599eeae96dd88bc upstream.

In journal_reclaim() ja-&gt;cur_idx of each cache will be update to
reclaim available journal buckets. Variable 'int n' is used to count how
many cache is successfully reclaimed, then n is set to c-&gt;journal.key
by SET_KEY_PTRS(). Later in journal_write_unlocked(), a for_each_cache()
loop will write the jset data onto each cache.

The problem is, if all jouranl buckets on each cache is full, the
following code in journal_reclaim(),

529 for_each_cache(ca, c, iter) {
530       struct journal_device *ja = &amp;ca-&gt;journal;
531       unsigned int next = (ja-&gt;cur_idx + 1) % ca-&gt;sb.njournal_buckets;
532
533       /* No space available on this device */
534       if (next == ja-&gt;discard_idx)
535               continue;
536
537       ja-&gt;cur_idx = next;
538       k-&gt;ptr[n++] = MAKE_PTR(0,
539                         bucket_to_sector(c, ca-&gt;sb.d[ja-&gt;cur_idx]),
540                         ca-&gt;sb.nr_this_dev);
541 }
542
543 bkey_init(k);
544 SET_KEY_PTRS(k, n);

If there is no available bucket to reclaim, the if() condition at line
534 will always true, and n remains 0. Then at line 544, SET_KEY_PTRS()
will set KEY_PTRS field of c-&gt;journal.key to 0.

Setting KEY_PTRS field of c-&gt;journal.key to 0 is wrong. Because in
journal_write_unlocked() the journal data is written in following loop,

649	for (i = 0; i &lt; KEY_PTRS(k); i++) {
650-671		submit journal data to cache device
672	}

If KEY_PTRS field is set to 0 in jouranl_reclaim(), the journal data
won't be written to cache device here. If system crahed or rebooted
before bkeys of the lost journal entries written into btree nodes, data
corruption will be reported during bcache reload after rebooting the
system.

Indeed there is only one cache in a cache set, there is no need to set
KEY_PTRS field in journal_reclaim() at all. But in order to keep the
for_each_cache() logic consistent for now, this patch fixes the above
problem by not setting 0 KEY_PTRS of journal key, if there is no bucket
available to reclaim.

Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: fix a race between cache register and cacheset unregister</title>
<updated>2019-05-22T05:39:54+00:00</updated>
<author>
<name>Liang Chen</name>
<email>liangchen.linux@gmail.com</email>
</author>
<published>2019-04-24T16:48:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=41f891ee7d43004c31cd9c8c61bacf9e3c118369'/>
<id>41f891ee7d43004c31cd9c8c61bacf9e3c118369</id>
<content type='text'>
commit a4b732a248d12cbdb46999daf0bf288c011335eb upstream.

There is a race between cache device register and cache set unregister.
For an already registered cache device, register_bcache will call
bch_is_open to iterate through all cachesets and check every cache
there. The race occurs if cache_set_free executes at the same time and
clears the caches right before ca is dereferenced in bch_is_open_cache.
To close the race, let's make sure the clean up work is protected by
the bch_register_lock as well.

This issue can be reproduced as follows,
while true; do echo /dev/XXX&gt; /sys/fs/bcache/register ; done&amp;
while true; do echo 1&gt; /sys/block/XXX/bcache/set/unregister ; done &amp;

and results in the following oops,

[  +0.000053] BUG: unable to handle kernel NULL pointer dereference at 0000000000000998
[  +0.000457] #PF error: [normal kernel read fault]
[  +0.000464] PGD 800000003ca9d067 P4D 800000003ca9d067 PUD 3ca9c067 PMD 0
[  +0.000388] Oops: 0000 [#1] SMP PTI
[  +0.000269] CPU: 1 PID: 3266 Comm: bash Not tainted 5.0.0+ #6
[  +0.000346] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.fc28 04/01/2014
[  +0.000472] RIP: 0010:register_bcache+0x1829/0x1990 [bcache]
[  +0.000344] Code: b0 48 83 e8 50 48 81 fa e0 e1 10 c0 0f 84 a9 00 00 00 48 89 c6 48 89 ca 0f b7 ba 54 04 00 00 4c 8b 82 60 0c 00 00 85 ff 74 2f &lt;49&gt; 3b a8 98 09 00 00 74 4e 44 8d 47 ff 31 ff 49 c1 e0 03 eb 0d
[  +0.000839] RSP: 0018:ffff92ee804cbd88 EFLAGS: 00010202
[  +0.000328] RAX: ffffffffc010e190 RBX: ffff918b5c6b5000 RCX: ffff918b7d8e0000
[  +0.000399] RDX: ffff918b7d8e0000 RSI: ffffffffc010e190 RDI: 0000000000000001
[  +0.000398] RBP: ffff918b7d318340 R08: 0000000000000000 R09: ffffffffb9bd2d7a
[  +0.000385] R10: ffff918b7eb253c0 R11: ffffb95980f51200 R12: ffffffffc010e1a0
[  +0.000411] R13: fffffffffffffff2 R14: 000000000000000b R15: ffff918b7e232620
[  +0.000384] FS:  00007f955bec2740(0000) GS:ffff918b7eb00000(0000) knlGS:0000000000000000
[  +0.000420] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  +0.000801] CR2: 0000000000000998 CR3: 000000003cad6000 CR4: 00000000001406e0
[  +0.000837] Call Trace:
[  +0.000682]  ? _cond_resched+0x10/0x20
[  +0.000691]  ? __kmalloc+0x131/0x1b0
[  +0.000710]  kernfs_fop_write+0xfa/0x170
[  +0.000733]  __vfs_write+0x2e/0x190
[  +0.000688]  ? inode_security+0x10/0x30
[  +0.000698]  ? selinux_file_permission+0xd2/0x120
[  +0.000752]  ? security_file_permission+0x2b/0x100
[  +0.000753]  vfs_write+0xa8/0x1a0
[  +0.000676]  ksys_write+0x4d/0xb0
[  +0.000699]  do_syscall_64+0x3a/0xf0
[  +0.000692]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a4b732a248d12cbdb46999daf0bf288c011335eb upstream.

There is a race between cache device register and cache set unregister.
For an already registered cache device, register_bcache will call
bch_is_open to iterate through all cachesets and check every cache
there. The race occurs if cache_set_free executes at the same time and
clears the caches right before ca is dereferenced in bch_is_open_cache.
To close the race, let's make sure the clean up work is protected by
the bch_register_lock as well.

This issue can be reproduced as follows,
while true; do echo /dev/XXX&gt; /sys/fs/bcache/register ; done&amp;
while true; do echo 1&gt; /sys/block/XXX/bcache/set/unregister ; done &amp;

and results in the following oops,

[  +0.000053] BUG: unable to handle kernel NULL pointer dereference at 0000000000000998
[  +0.000457] #PF error: [normal kernel read fault]
[  +0.000464] PGD 800000003ca9d067 P4D 800000003ca9d067 PUD 3ca9c067 PMD 0
[  +0.000388] Oops: 0000 [#1] SMP PTI
[  +0.000269] CPU: 1 PID: 3266 Comm: bash Not tainted 5.0.0+ #6
[  +0.000346] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.fc28 04/01/2014
[  +0.000472] RIP: 0010:register_bcache+0x1829/0x1990 [bcache]
[  +0.000344] Code: b0 48 83 e8 50 48 81 fa e0 e1 10 c0 0f 84 a9 00 00 00 48 89 c6 48 89 ca 0f b7 ba 54 04 00 00 4c 8b 82 60 0c 00 00 85 ff 74 2f &lt;49&gt; 3b a8 98 09 00 00 74 4e 44 8d 47 ff 31 ff 49 c1 e0 03 eb 0d
[  +0.000839] RSP: 0018:ffff92ee804cbd88 EFLAGS: 00010202
[  +0.000328] RAX: ffffffffc010e190 RBX: ffff918b5c6b5000 RCX: ffff918b7d8e0000
[  +0.000399] RDX: ffff918b7d8e0000 RSI: ffffffffc010e190 RDI: 0000000000000001
[  +0.000398] RBP: ffff918b7d318340 R08: 0000000000000000 R09: ffffffffb9bd2d7a
[  +0.000385] R10: ffff918b7eb253c0 R11: ffffb95980f51200 R12: ffffffffc010e1a0
[  +0.000411] R13: fffffffffffffff2 R14: 000000000000000b R15: ffff918b7e232620
[  +0.000384] FS:  00007f955bec2740(0000) GS:ffff918b7eb00000(0000) knlGS:0000000000000000
[  +0.000420] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  +0.000801] CR2: 0000000000000998 CR3: 000000003cad6000 CR4: 00000000001406e0
[  +0.000837] Call Trace:
[  +0.000682]  ? _cond_resched+0x10/0x20
[  +0.000691]  ? __kmalloc+0x131/0x1b0
[  +0.000710]  kernfs_fop_write+0xfa/0x170
[  +0.000733]  __vfs_write+0x2e/0x190
[  +0.000688]  ? inode_security+0x10/0x30
[  +0.000698]  ? selinux_file_permission+0xd2/0x120
[  +0.000752]  ? security_file_permission+0x2b/0x100
[  +0.000753]  vfs_write+0xa8/0x1a0
[  +0.000676]  ksys_write+0x4d/0xb0
[  +0.000699]  do_syscall_64+0x3a/0xf0
[  +0.000692]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>tty/vt: fix write/write race in ioctl(KDSKBSENT) handler</title>
<updated>2019-05-22T05:39:52+00:00</updated>
<author>
<name>Sergei Trofimovich</name>
<email>slyfox@gentoo.org</email>
</author>
<published>2019-03-10T21:24:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ed1d236d7dac01bc202697fbad0ccf6e76914b46'/>
<id>ed1d236d7dac01bc202697fbad0ccf6e76914b46</id>
<content type='text'>
commit 46ca3f735f345c9d87383dd3a09fa5d43870770e upstream.

The bug manifests as an attempt to access deallocated memory:

    BUG: unable to handle kernel paging request at ffff9c8735448000
    #PF error: [PROT] [WRITE]
    PGD 288a05067 P4D 288a05067 PUD 288a07067 PMD 7f60c2063 PTE 80000007f5448161
    Oops: 0003 [#1] PREEMPT SMP
    CPU: 6 PID: 388 Comm: loadkeys Tainted: G         C        5.0.0-rc6-00153-g5ded5871030e #91
    Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M-D3H, BIOS F12 11/14/2013
    RIP: 0010:__memmove+0x81/0x1a0
    Code: 4c 89 4f 10 4c 89 47 18 48 8d 7f 20 73 d4 48 83 c2 20 e9 a2 00 00 00 66 90 48 89 d1 4c 8b 5c 16 f8 4c 8d 54 17 f8 48 c1 e9 03 &lt;f3&gt; 48 a5 4d 89 1a e9 0c 01 00 00 0f 1f 40 00 48 89 d1 4c 8b 1e 49
    RSP: 0018:ffffa1b9002d7d08 EFLAGS: 00010203
    RAX: ffff9c873541af43 RBX: ffff9c873541af43 RCX: 00000c6f105cd6bf
    RDX: 0000637882e986b6 RSI: ffff9c8735447ffb RDI: ffff9c8735447ffb
    RBP: ffff9c8739cd3800 R08: ffff9c873b802f00 R09: 00000000fffff73b
    R10: ffffffffb82b35f1 R11: 00505b1b004d5b1b R12: 0000000000000000
    R13: ffff9c873541af3d R14: 000000000000000b R15: 000000000000000c
    FS:  00007f450c390580(0000) GS:ffff9c873f180000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffff9c8735448000 CR3: 00000007e213c002 CR4: 00000000000606e0
    Call Trace:
     vt_do_kdgkb_ioctl+0x34d/0x440
     vt_ioctl+0xba3/0x1190
     ? __bpf_prog_run32+0x39/0x60
     ? mem_cgroup_commit_charge+0x7b/0x4e0
     tty_ioctl+0x23f/0x920
     ? preempt_count_sub+0x98/0xe0
     ? __seccomp_filter+0x67/0x600
     do_vfs_ioctl+0xa2/0x6a0
     ? syscall_trace_enter+0x192/0x2d0
     ksys_ioctl+0x3a/0x70
     __x64_sys_ioctl+0x16/0x20
     do_syscall_64+0x54/0xe0
     entry_SYSCALL_64_after_hwframe+0x49/0xbe

The bug manifests on systemd systems with multiple vtcon devices:
  # cat /sys/devices/virtual/vtconsole/vtcon0/name
  (S) dummy device
  # cat /sys/devices/virtual/vtconsole/vtcon1/name
  (M) frame buffer device

There systemd runs 'loadkeys' tool in tapallel for each vtcon
instance. This causes two parallel ioctl(KDSKBSENT) calls to
race into adding the same entry into 'func_table' array at:

    drivers/tty/vt/keyboard.c:vt_do_kdgkb_ioctl()

The function has no locking around writes to 'func_table'.

The simplest reproducer is to have initrams with the following
init on a 8-CPU machine x86_64:

    #!/bin/sh

    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;

    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    wait

The change adds lock on write path only. Reads are still racy.

CC: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
CC: Jiri Slaby &lt;jslaby@suse.com&gt;
Link: https://lkml.org/lkml/2019/2/17/256
Signed-off-by: Sergei Trofimovich &lt;slyfox@gentoo.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 46ca3f735f345c9d87383dd3a09fa5d43870770e upstream.

The bug manifests as an attempt to access deallocated memory:

    BUG: unable to handle kernel paging request at ffff9c8735448000
    #PF error: [PROT] [WRITE]
    PGD 288a05067 P4D 288a05067 PUD 288a07067 PMD 7f60c2063 PTE 80000007f5448161
    Oops: 0003 [#1] PREEMPT SMP
    CPU: 6 PID: 388 Comm: loadkeys Tainted: G         C        5.0.0-rc6-00153-g5ded5871030e #91
    Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M-D3H, BIOS F12 11/14/2013
    RIP: 0010:__memmove+0x81/0x1a0
    Code: 4c 89 4f 10 4c 89 47 18 48 8d 7f 20 73 d4 48 83 c2 20 e9 a2 00 00 00 66 90 48 89 d1 4c 8b 5c 16 f8 4c 8d 54 17 f8 48 c1 e9 03 &lt;f3&gt; 48 a5 4d 89 1a e9 0c 01 00 00 0f 1f 40 00 48 89 d1 4c 8b 1e 49
    RSP: 0018:ffffa1b9002d7d08 EFLAGS: 00010203
    RAX: ffff9c873541af43 RBX: ffff9c873541af43 RCX: 00000c6f105cd6bf
    RDX: 0000637882e986b6 RSI: ffff9c8735447ffb RDI: ffff9c8735447ffb
    RBP: ffff9c8739cd3800 R08: ffff9c873b802f00 R09: 00000000fffff73b
    R10: ffffffffb82b35f1 R11: 00505b1b004d5b1b R12: 0000000000000000
    R13: ffff9c873541af3d R14: 000000000000000b R15: 000000000000000c
    FS:  00007f450c390580(0000) GS:ffff9c873f180000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffff9c8735448000 CR3: 00000007e213c002 CR4: 00000000000606e0
    Call Trace:
     vt_do_kdgkb_ioctl+0x34d/0x440
     vt_ioctl+0xba3/0x1190
     ? __bpf_prog_run32+0x39/0x60
     ? mem_cgroup_commit_charge+0x7b/0x4e0
     tty_ioctl+0x23f/0x920
     ? preempt_count_sub+0x98/0xe0
     ? __seccomp_filter+0x67/0x600
     do_vfs_ioctl+0xa2/0x6a0
     ? syscall_trace_enter+0x192/0x2d0
     ksys_ioctl+0x3a/0x70
     __x64_sys_ioctl+0x16/0x20
     do_syscall_64+0x54/0xe0
     entry_SYSCALL_64_after_hwframe+0x49/0xbe

The bug manifests on systemd systems with multiple vtcon devices:
  # cat /sys/devices/virtual/vtconsole/vtcon0/name
  (S) dummy device
  # cat /sys/devices/virtual/vtconsole/vtcon1/name
  (M) frame buffer device

There systemd runs 'loadkeys' tool in tapallel for each vtcon
instance. This causes two parallel ioctl(KDSKBSENT) calls to
race into adding the same entry into 'func_table' array at:

    drivers/tty/vt/keyboard.c:vt_do_kdgkb_ioctl()

The function has no locking around writes to 'func_table'.

The simplest reproducer is to have initrams with the following
init on a 8-CPU machine x86_64:

    #!/bin/sh

    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;

    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    loadkeys -q windowkeys ru4 &amp;
    wait

The change adds lock on write path only. Reads are still racy.

CC: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
CC: Jiri Slaby &lt;jslaby@suse.com&gt;
Link: https://lkml.org/lkml/2019/2/17/256
Signed-off-by: Sergei Trofimovich &lt;slyfox@gentoo.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>tty: vt.c: Fix TIOCL_BLANKSCREEN console blanking if blankinterval == 0</title>
<updated>2019-05-22T05:39:52+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-03-04T23:02:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f5eaf86b41442af176d317c56823665f9850939e'/>
<id>f5eaf86b41442af176d317c56823665f9850939e</id>
<content type='text'>
commit 75ddbc1fb11efac87b611d48e9802f6fe2bb2163 upstream.

Previously, in the userspace, it was possible to use the "setterm" command
from util-linux to blank the VT console by default, using the following
command.

According to the man page,

&gt; The force option keeps the screen blank even if a key is pressed.

It was implemented by calling TIOCL_BLANKSCREEN.

	case BLANKSCREEN:
		ioctlarg = TIOCL_BLANKSCREEN;
		if (ioctl(STDIN_FILENO, TIOCLINUX, &amp;ioctlarg))
			warn(_("cannot force blank"));
		break;

However, after Linux 4.12, this command ceased to work anymore, which is
unexpected. By inspecting the kernel source, it shows that the issue was
triggered by the side-effect from commit a4199f5eb809 ("tty: Disable
default console blanking interval").

The console blanking is implemented by function do_blank_screen() in vt.c:
"blank_state" will be initialized to "blank_normal_wait" in con_init() if
AND ONLY IF ("blankinterval" &gt; 0). If "blankinterval" is 0, "blank_state"
will be "blank_off" (== 0), and a call to do_blank_screen() will always
abort, even if a forced blanking is required from the user by calling
TIOCL_BLANKSCREEN, the console won't be blanked.

This behavior is unexpected from a user's point-of-view, since it's not
mentioned in any documentation. The setterm man page suggests it will
always work, and the kernel comments in uapi/linux/tiocl.h says

&gt; /* keep screen blank even if a key is pressed */
&gt; #define TIOCL_BLANKSCREEN 14

To fix it, we simply remove the "blank_state != blank_off" check, as
pointed out by Nicolas Pitre, this check doesn't logically make sense
and it's safe to remove.

Suggested-by: Nicolas Pitre &lt;nicolas.pitre@linaro.org&gt;
Fixes: a4199f5eb809 ("tty: Disable default console blanking interval")
Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 75ddbc1fb11efac87b611d48e9802f6fe2bb2163 upstream.

Previously, in the userspace, it was possible to use the "setterm" command
from util-linux to blank the VT console by default, using the following
command.

According to the man page,

&gt; The force option keeps the screen blank even if a key is pressed.

It was implemented by calling TIOCL_BLANKSCREEN.

	case BLANKSCREEN:
		ioctlarg = TIOCL_BLANKSCREEN;
		if (ioctl(STDIN_FILENO, TIOCLINUX, &amp;ioctlarg))
			warn(_("cannot force blank"));
		break;

However, after Linux 4.12, this command ceased to work anymore, which is
unexpected. By inspecting the kernel source, it shows that the issue was
triggered by the side-effect from commit a4199f5eb809 ("tty: Disable
default console blanking interval").

The console blanking is implemented by function do_blank_screen() in vt.c:
"blank_state" will be initialized to "blank_normal_wait" in con_init() if
AND ONLY IF ("blankinterval" &gt; 0). If "blankinterval" is 0, "blank_state"
will be "blank_off" (== 0), and a call to do_blank_screen() will always
abort, even if a forced blanking is required from the user by calling
TIOCL_BLANKSCREEN, the console won't be blanked.

This behavior is unexpected from a user's point-of-view, since it's not
mentioned in any documentation. The setterm man page suggests it will
always work, and the kernel comments in uapi/linux/tiocl.h says

&gt; /* keep screen blank even if a key is pressed */
&gt; #define TIOCL_BLANKSCREEN 14

To fix it, we simply remove the "blank_state != blank_off" check, as
pointed out by Nicolas Pitre, this check doesn't logically make sense
and it's safe to remove.

Suggested-by: Nicolas Pitre &lt;nicolas.pitre@linaro.org&gt;
Fixes: a4199f5eb809 ("tty: Disable default console blanking interval")
Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: maps: Allow MTD_PHYSMAP with MTD_RAM</title>
<updated>2019-05-22T05:39:52+00:00</updated>
<author>
<name>Chris Packham</name>
<email>chris.packham@alliedtelesis.co.nz</email>
</author>
<published>2019-04-03T02:02:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=df94497492a9a1589fc231324aa3b4fb2ed359f6'/>
<id>df94497492a9a1589fc231324aa3b4fb2ed359f6</id>
<content type='text'>
commit d41970097f10d898cef0eb04bf53d786efd6bbbc upstream.

When the physmap_of_core.c code was merged into physmap-core.c the
ability to use MTD_PHYSMAP_OF with only MTD_RAM selected was lost.
Restore this by adding MTD_RAM to the dependencies of MTD_PHYSMAP.

Fixes: commit 642b1e8dbed7 ("mtd: maps: Merge physmap_of.c into physmap-core.c")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Reviewed-by: Hamish Martin &lt;hamish.martin@alliedtelesis.co.nz&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d41970097f10d898cef0eb04bf53d786efd6bbbc upstream.

When the physmap_of_core.c code was merged into physmap-core.c the
ability to use MTD_PHYSMAP_OF with only MTD_RAM selected was lost.
Restore this by adding MTD_RAM to the dependencies of MTD_PHYSMAP.

Fixes: commit 642b1e8dbed7 ("mtd: maps: Merge physmap_of.c into physmap-core.c")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Reviewed-by: Hamish Martin &lt;hamish.martin@alliedtelesis.co.nz&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: maps: physmap: Store gpio_values correctly</title>
<updated>2019-05-22T05:39:52+00:00</updated>
<author>
<name>Chris Packham</name>
<email>chris.packham@alliedtelesis.co.nz</email>
</author>
<published>2019-03-29T02:13:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b429d215a58f377c28d5e0174cfd9d423b00691'/>
<id>8b429d215a58f377c28d5e0174cfd9d423b00691</id>
<content type='text'>
commit 64d14c6fe040361ff6aecb825e392cf97837cd9e upstream.

When the gpio-addr-flash.c driver was merged with physmap-core.c the
code to store the current gpio_values was lost. This meant that once a
gpio was asserted it was never de-asserted. Fix this by storing the
current offset in gpio_values like the old driver used to.

Fixes: commit ba32ce95cbd9 ("mtd: maps: Merge gpio-addr-flash.c into physmap-core.c")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Reviewed-by: Boris Brezillon &lt;boris.brezillon@collabora.com&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 64d14c6fe040361ff6aecb825e392cf97837cd9e upstream.

When the gpio-addr-flash.c driver was merged with physmap-core.c the
code to store the current gpio_values was lost. This meant that once a
gpio was asserted it was never de-asserted. Fix this by storing the
current offset in gpio_values like the old driver used to.

Fixes: commit ba32ce95cbd9 ("mtd: maps: Merge gpio-addr-flash.c into physmap-core.c")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Reviewed-by: Boris Brezillon &lt;boris.brezillon@collabora.com&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
