<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/block/ps3disk.c, branch v6.12-rc4</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>block: move the nonrot flag to queue_limits</title>
<updated>2024-06-19T13:58:28+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-06-17T06:04:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bd4a633b6f7c3c6b6ebc1a07317643270e751a94'/>
<id>bd4a633b6f7c3c6b6ebc1a07317643270e751a94</id>
<content type='text'>
Move the nonrot flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.

Use the chance to switch to defaulting to non-rotational and require
the driver to opt into rotational, which matches the polarity of the
sysfs interface.

For the z2ram, ps3vram, 2x memstick, ubiblock and dcssblk the new
rotational flag is not set as they clearly are not rotational despite
this being a behavior change.  There are some other drivers that
unconditionally set the rotational flag to keep the existing behavior
as they arguably can be used on rotational devices even if that is
probably not their main use today (e.g. virtio_blk and drbd).

The flag is automatically inherited in blk_stack_limits matching the
existing behavior in dm and md.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240617060532.127975-15-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the nonrot flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.

Use the chance to switch to defaulting to non-rotational and require
the driver to opt into rotational, which matches the polarity of the
sysfs interface.

For the z2ram, ps3vram, 2x memstick, ubiblock and dcssblk the new
rotational flag is not set as they clearly are not rotational despite
this being a behavior change.  There are some other drivers that
unconditionally set the rotational flag to keep the existing behavior
as they arguably can be used on rotational devices even if that is
probably not their main use today (e.g. virtio_blk and drbd).

The flag is automatically inherited in blk_stack_limits matching the
existing behavior in dm and md.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240617060532.127975-15-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: move cache control settings out of queue-&gt;flags</title>
<updated>2024-06-19T13:58:28+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-06-17T06:04:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1122c0c1cc71f740fa4d5f14f239194e06a1d5e7'/>
<id>1122c0c1cc71f740fa4d5f14f239194e06a1d5e7</id>
<content type='text'>
Move the cache control settings into the queue_limits so that the flags
can be set atomically with the device queue frozen.

Add new features and flags field for the driver set flags, and internal
(usually sysfs-controlled) flags in the block layer.  Note that we'll
eventually remove enough field from queue_limits to bring it back to the
previous size.

The disable flag is inverted compared to the previous meaning, which
means it now survives a rescan, similar to the max_sectors and
max_discard_sectors user limits.

The FLUSH and FUA flags are now inherited by blk_stack_limits, which
simplified the code in dm a lot, but also causes a slight behavior
change in that dm-switch and dm-unstripe now advertise a write cache
despite setting num_flush_bios to 0.  The I/O path will handle this
gracefully, but as far as I can tell the lack of num_flush_bios
and thus flush support is a pre-existing data integrity bug in those
targets that really needs fixing, after which a non-zero num_flush_bios
should be required in dm for targets that map to underlying devices.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the cache control settings into the queue_limits so that the flags
can be set atomically with the device queue frozen.

Add new features and flags field for the driver set flags, and internal
(usually sysfs-controlled) flags in the block layer.  Note that we'll
eventually remove enough field from queue_limits to bring it back to the
previous size.

The disable flag is inverted compared to the previous meaning, which
means it now survives a rescan, similar to the max_sectors and
max_discard_sectors user limits.

The FLUSH and FUA flags are now inherited by blk_stack_limits, which
simplified the code in dm a lot, but also causes a slight behavior
change in that dm-switch and dm-unstripe now advertise a write cache
despite setting num_flush_bios to 0.  The I/O path will handle this
gracefully, but as far as I can tell the lack of num_flush_bios
and thus flush support is a pre-existing data integrity bug in those
targets that really needs fixing, after which a non-zero num_flush_bios
should be required in dm for targets that map to underlying devices.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: pass queue_limits to blk_mq_alloc_disk</title>
<updated>2024-02-19T23:59:31+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-02-15T07:02:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a7f18b74dbe171625afc2751942a92f71a4dd4ba'/>
<id>a7f18b74dbe171625afc2751942a92f71a4dd4ba</id>
<content type='text'>
Pass the few limits ps3disk imposes directly to blk_mq_alloc_disk instead
of setting them one at a time.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/20240215070300.2200308-7-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pass the few limits ps3disk imposes directly to blk_mq_alloc_disk instead
of setting them one at a time.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/20240215070300.2200308-7-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: pass a queue_limits argument to blk_mq_alloc_disk</title>
<updated>2024-02-13T15:56:59+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-02-13T07:34:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=27e32cd23fed1ab88098897897dcb9ec2bdba4de'/>
<id>27e32cd23fed1ab88098897897dcb9ec2bdba4de</id>
<content type='text'>
Pass a queue_limits to blk_mq_alloc_disk and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Keith Busch &lt;kbusch@kernel.org&gt;
Reviewed-by: John Garry &lt;john.g.garry@oracle.com&gt;
Reviewed-by: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240213073425.1621680-11-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pass a queue_limits to blk_mq_alloc_disk and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Keith Busch &lt;kbusch@kernel.org&gt;
Reviewed-by: John Garry &lt;john.g.garry@oracle.com&gt;
Reviewed-by: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20240213073425.1621680-11-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: remove blk_cleanup_disk</title>
<updated>2022-06-28T12:33:15+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2022-06-19T06:05:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8b9ab62662048a3274361c7e5f64037c2c133e2c'/>
<id>8b9ab62662048a3274361c7e5f64037c2c133e2c</id>
<content type='text'>
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: add error handling support for add_disk()</title>
<updated>2021-10-30T17:03:37+00:00</updated>
<author>
<name>Luis Chamberlain</name>
<email>mcgrof@kernel.org</email>
</author>
<published>2021-10-15T23:52:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ff4cbe0fcf5d749f76040f782f0618656cd23e33'/>
<id>ff4cbe0fcf5d749f76040f782f0618656cd23e33</id>
<content type='text'>
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

Signed-off-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Link: https://lore.kernel.org/r/20211015235219.2191207-11-mcgrof@kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

Signed-off-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Link: https://lore.kernel.org/r/20211015235219.2191207-11-mcgrof@kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: use memcpy_{from,to}_bvec</title>
<updated>2021-08-02T19:37:27+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2021-07-27T05:56:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6e0a48552b8cfc3767b98e3e8beed3f4cbafc9f4'/>
<id>6e0a48552b8cfc3767b98e3e8beed3f4cbafc9f4</id>
<content type='text'>
Use the bvec helpers instead of open coding the copy.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Link: https://lore.kernel.org/r/20210727055646.118787-9-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use the bvec helpers instead of open coding the copy.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Link: https://lore.kernel.org/r/20210727055646.118787-9-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: use blk_mq_alloc_disk</title>
<updated>2021-06-11T17:53:02+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2021-06-02T06:53:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=89662ac55a204d82f9b0c1497e060d18b51fadc2'/>
<id>89662ac55a204d82f9b0c1497e060d18b51fadc2</id>
<content type='text'>
Use the blk_mq_alloc_disk API to simplify the gendisk and request_queue
allocation.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Reviewed-by: Chaitanya Kulkarni &lt;chaitanya.kulkarni@wdc.com&gt;
Link: https://lore.kernel.org/r/20210602065345.355274-11-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use the blk_mq_alloc_disk API to simplify the gendisk and request_queue
allocation.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Tested-by: Geoff Levand &lt;geoff@infradead.org&gt;
Reviewed-by: Chaitanya Kulkarni &lt;chaitanya.kulkarni@wdc.com&gt;
Link: https://lore.kernel.org/r/20210602065345.355274-11-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/ps3: make system bus's remove and shutdown callbacks return void</title>
<updated>2020-12-03T14:01:22+00:00</updated>
<author>
<name>Uwe Kleine-König</name>
<email>u.kleine-koenig@pengutronix.de</email>
</author>
<published>2020-11-26T16:59:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6d247e4d264961aa3b871290f9b11a48d5a567f2'/>
<id>6d247e4d264961aa3b871290f9b11a48d5a567f2</id>
<content type='text'>
The driver core ignores the return value of struct device_driver::remove
because there is only little that can be done. For the shutdown callback
it's ps3_system_bus_shutdown() which ignores the return value.

To simplify the quest to make struct device_driver::remove return void,
let struct ps3_system_bus_driver::remove return void, too. All users
already unconditionally return 0, this commit makes it obvious that
returning an error code is a bad idea and ensures future users behave
accordingly.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Acked-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20201126165950.2554997-2-u.kleine-koenig@pengutronix.de
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The driver core ignores the return value of struct device_driver::remove
because there is only little that can be done. For the shutdown callback
it's ps3_system_bus_shutdown() which ignores the return value.

To simplify the quest to make struct device_driver::remove return void,
let struct ps3_system_bus_driver::remove return void, too. All users
already unconditionally return 0, this commit makes it obvious that
returning an error code is a bad idea and ensures future users behave
accordingly.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Acked-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20201126165950.2554997-2-u.kleine-koenig@pengutronix.de
</pre>
</div>
</content>
</entry>
<entry>
<title>ps3disk: use the default segment boundary</title>
<updated>2020-05-18T14:10:35+00:00</updated>
<author>
<name>Emmanuel Nicolet</name>
<email>emmanuel.nicolet@gmail.com</email>
</author>
<published>2020-05-09T18:58:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=720bc316690bd27dea9d71510b50f0cd698ffc32'/>
<id>720bc316690bd27dea9d71510b50f0cd698ffc32</id>
<content type='text'>
Since commit dcebd755926b ("block: use bio_for_each_bvec() to compute
multi-page bvec count"), the kernel will bug_on on the PS3 because
bio_split() is called with sectors == 0:

  kernel BUG at block/bio.c:1853!
  Oops: Exception in kernel mode, sig: 5 [#1]
  BE PAGE_SIZE=4K MMU=Hash PREEMPT SMP NR_CPUS=8 NUMA PS3
  Modules linked in: firewire_sbp2 rtc_ps3(+) soundcore ps3_gelic(+) \
  ps3rom(+) firewire_core ps3vram(+) usb_common crc_itu_t
  CPU: 0 PID: 97 Comm: blkid Not tainted 5.3.0-rc4 #1
  NIP:  c00000000027d0d0 LR: c00000000027d0b0 CTR: 0000000000000000
  REGS: c00000000135ae90 TRAP: 0700   Not tainted  (5.3.0-rc4)
  MSR:  8000000000028032 &lt;SF,EE,IR,DR,RI&gt;  CR: 44008240  XER: 20000000
  IRQMASK: 0
  GPR00: c000000000289368 c00000000135b120 c00000000084a500 c000000004ff8300
  GPR04: 0000000000000c00 c000000004c905e0 c000000004c905e0 000000000000ffff
  GPR08: 0000000000000000 0000000000000001 0000000000000000 000000000000ffff
  GPR12: 0000000000000000 c0000000008ef000 000000000000003e 0000000000080001
  GPR16: 0000000000000100 000000000000ffff 0000000000000000 0000000000000004
  GPR20: c00000000062fd7e 0000000000000001 000000000000ffff 0000000000000080
  GPR24: c000000000781788 c00000000135b350 0000000000000080 c000000004c905e0
  GPR28: c00000000135b348 c000000004ff8300 0000000000000000 c000000004c90000
  NIP [c00000000027d0d0] .bio_split+0x28/0xac
  LR [c00000000027d0b0] .bio_split+0x8/0xac
  Call Trace:
  [c00000000135b120] [c00000000027d130] .bio_split+0x88/0xac (unreliable)
  [c00000000135b1b0] [c000000000289368] .__blk_queue_split+0x11c/0x53c
  [c00000000135b2d0] [c00000000028f614] .blk_mq_make_request+0x80/0x7d4
  [c00000000135b3d0] [c000000000283a8c] .generic_make_request+0x118/0x294
  [c00000000135b4b0] [c000000000283d34] .submit_bio+0x12c/0x174
  [c00000000135b580] [c000000000205a44] .mpage_bio_submit+0x3c/0x4c
  [c00000000135b600] [c000000000206184] .mpage_readpages+0xa4/0x184
  [c00000000135b750] [c0000000001ff8fc] .blkdev_readpages+0x24/0x38
  [c00000000135b7c0] [c0000000001589f0] .read_pages+0x6c/0x1a8
  [c00000000135b8b0] [c000000000158c74] .__do_page_cache_readahead+0x118/0x184
  [c00000000135b9b0] [c0000000001591a8] .force_page_cache_readahead+0xe4/0xe8
  [c00000000135ba50] [c00000000014fc24] .generic_file_read_iter+0x1d8/0x830
  [c00000000135bb50] [c0000000001ffadc] .blkdev_read_iter+0x40/0x5c
  [c00000000135bbc0] [c0000000001b9e00] .new_sync_read+0x144/0x1a0
  [c00000000135bcd0] [c0000000001bc454] .vfs_read+0xa0/0x124
  [c00000000135bd70] [c0000000001bc7a4] .ksys_read+0x70/0xd8
  [c00000000135be20] [c00000000000a524] system_call+0x5c/0x70
  Instruction dump:
  7fe3fb78 482e30dc 7c0802a6 482e3085 7c9e2378 f821ff71 7ca42b78 7d3e00d0
  7c7d1b78 79290fe0 7cc53378 69290001 &lt;0b090000&gt; 81230028 7bca0020 7929ba62
  [ end trace 313fec760f30aa1f ]---

The problem originates from setting the segment boundary of the
request queue to -1UL. This makes get_max_segment_size() return zero
when offset is zero, whatever the max segment size. The test with
BLK_SEG_BOUNDARY_MASK fails and 'mask - (mask &amp; offset) + 1' overflows
to zero in the return statement.

Not setting the segment boundary and using the default
value (BLK_SEG_BOUNDARY_MASK) fixes the problem.

Signed-off-by: Emmanuel Nicolet &lt;emmanuel.nicolet@gmail.com&gt;
Signed-off-by: Geoff Levand &lt;geoff@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/060a416c43138f45105c0540eff1a45539f7e2fc.1589049250.git.geoff@infradead.org
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since commit dcebd755926b ("block: use bio_for_each_bvec() to compute
multi-page bvec count"), the kernel will bug_on on the PS3 because
bio_split() is called with sectors == 0:

  kernel BUG at block/bio.c:1853!
  Oops: Exception in kernel mode, sig: 5 [#1]
  BE PAGE_SIZE=4K MMU=Hash PREEMPT SMP NR_CPUS=8 NUMA PS3
  Modules linked in: firewire_sbp2 rtc_ps3(+) soundcore ps3_gelic(+) \
  ps3rom(+) firewire_core ps3vram(+) usb_common crc_itu_t
  CPU: 0 PID: 97 Comm: blkid Not tainted 5.3.0-rc4 #1
  NIP:  c00000000027d0d0 LR: c00000000027d0b0 CTR: 0000000000000000
  REGS: c00000000135ae90 TRAP: 0700   Not tainted  (5.3.0-rc4)
  MSR:  8000000000028032 &lt;SF,EE,IR,DR,RI&gt;  CR: 44008240  XER: 20000000
  IRQMASK: 0
  GPR00: c000000000289368 c00000000135b120 c00000000084a500 c000000004ff8300
  GPR04: 0000000000000c00 c000000004c905e0 c000000004c905e0 000000000000ffff
  GPR08: 0000000000000000 0000000000000001 0000000000000000 000000000000ffff
  GPR12: 0000000000000000 c0000000008ef000 000000000000003e 0000000000080001
  GPR16: 0000000000000100 000000000000ffff 0000000000000000 0000000000000004
  GPR20: c00000000062fd7e 0000000000000001 000000000000ffff 0000000000000080
  GPR24: c000000000781788 c00000000135b350 0000000000000080 c000000004c905e0
  GPR28: c00000000135b348 c000000004ff8300 0000000000000000 c000000004c90000
  NIP [c00000000027d0d0] .bio_split+0x28/0xac
  LR [c00000000027d0b0] .bio_split+0x8/0xac
  Call Trace:
  [c00000000135b120] [c00000000027d130] .bio_split+0x88/0xac (unreliable)
  [c00000000135b1b0] [c000000000289368] .__blk_queue_split+0x11c/0x53c
  [c00000000135b2d0] [c00000000028f614] .blk_mq_make_request+0x80/0x7d4
  [c00000000135b3d0] [c000000000283a8c] .generic_make_request+0x118/0x294
  [c00000000135b4b0] [c000000000283d34] .submit_bio+0x12c/0x174
  [c00000000135b580] [c000000000205a44] .mpage_bio_submit+0x3c/0x4c
  [c00000000135b600] [c000000000206184] .mpage_readpages+0xa4/0x184
  [c00000000135b750] [c0000000001ff8fc] .blkdev_readpages+0x24/0x38
  [c00000000135b7c0] [c0000000001589f0] .read_pages+0x6c/0x1a8
  [c00000000135b8b0] [c000000000158c74] .__do_page_cache_readahead+0x118/0x184
  [c00000000135b9b0] [c0000000001591a8] .force_page_cache_readahead+0xe4/0xe8
  [c00000000135ba50] [c00000000014fc24] .generic_file_read_iter+0x1d8/0x830
  [c00000000135bb50] [c0000000001ffadc] .blkdev_read_iter+0x40/0x5c
  [c00000000135bbc0] [c0000000001b9e00] .new_sync_read+0x144/0x1a0
  [c00000000135bcd0] [c0000000001bc454] .vfs_read+0xa0/0x124
  [c00000000135bd70] [c0000000001bc7a4] .ksys_read+0x70/0xd8
  [c00000000135be20] [c00000000000a524] system_call+0x5c/0x70
  Instruction dump:
  7fe3fb78 482e30dc 7c0802a6 482e3085 7c9e2378 f821ff71 7ca42b78 7d3e00d0
  7c7d1b78 79290fe0 7cc53378 69290001 &lt;0b090000&gt; 81230028 7bca0020 7929ba62
  [ end trace 313fec760f30aa1f ]---

The problem originates from setting the segment boundary of the
request queue to -1UL. This makes get_max_segment_size() return zero
when offset is zero, whatever the max segment size. The test with
BLK_SEG_BOUNDARY_MASK fails and 'mask - (mask &amp; offset) + 1' overflows
to zero in the return statement.

Not setting the segment boundary and using the default
value (BLK_SEG_BOUNDARY_MASK) fixes the problem.

Signed-off-by: Emmanuel Nicolet &lt;emmanuel.nicolet@gmail.com&gt;
Signed-off-by: Geoff Levand &lt;geoff@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/060a416c43138f45105c0540eff1a45539f7e2fc.1589049250.git.geoff@infradead.org
</pre>
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</content>
</entry>
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