<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/md/bcache, branch linux-6.3.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Merge tag 'flex-array-transformations-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux</title>
<updated>2023-02-25T20:53:42+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-02-25T20:53:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=472a2abb7af5067c45db25fb59c17e828af07886'/>
<id>472a2abb7af5067c45db25fb59c17e828af07886</id>
<content type='text'>
Pull flexible-array updates from Gustavo Silva:
 "Transform zero-length arrays, in unions, into flexible arrays"

* tag 'flex-array-transformations-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  bcache: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper
  mm/memremap: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
  exportfs: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull flexible-array updates from Gustavo Silva:
 "Transform zero-length arrays, in unions, into flexible arrays"

* tag 'flex-array-transformations-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  bcache: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper
  mm/memremap: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
  exportfs: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: Silence memcpy() run-time false positive warnings</title>
<updated>2023-01-25T20:24:50+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2023-01-06T06:02:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=be0d8f48ad97f5b775b0af3310343f676dbf318a'/>
<id>be0d8f48ad97f5b775b0af3310343f676dbf318a</id>
<content type='text'>
struct bkey has internal padding in a union, but it isn't always named
the same (e.g. key ## _pad, key_p, etc). This makes it extremely hard
for the compiler to reason about the available size of copies done
against such keys. Use unsafe_memcpy() for now, to silence the many
run-time false positive warnings:

  memcpy: detected field-spanning write (size 264) of single field "&amp;i-&gt;j" at drivers/md/bcache/journal.c:152 (size 240)
  memcpy: detected field-spanning write (size 24) of single field "&amp;b-&gt;key" at drivers/md/bcache/btree.c:939 (size 16)
  memcpy: detected field-spanning write (size 24) of single field "&amp;temp.key" at drivers/md/bcache/extents.c:428 (size 16)

Reported-by: Alexandre Pereira &lt;alexpereira@disroot.org&gt;
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216785
Acked-by: Coly Li &lt;colyli@suse.de&gt;
Cc: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20230106060229.never.047-kees@kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
struct bkey has internal padding in a union, but it isn't always named
the same (e.g. key ## _pad, key_p, etc). This makes it extremely hard
for the compiler to reason about the available size of copies done
against such keys. Use unsafe_memcpy() for now, to silence the many
run-time false positive warnings:

  memcpy: detected field-spanning write (size 264) of single field "&amp;i-&gt;j" at drivers/md/bcache/journal.c:152 (size 240)
  memcpy: detected field-spanning write (size 24) of single field "&amp;b-&gt;key" at drivers/md/bcache/btree.c:939 (size 16)
  memcpy: detected field-spanning write (size 24) of single field "&amp;temp.key" at drivers/md/bcache/extents.c:428 (size 16)

Reported-by: Alexandre Pereira &lt;alexpereira@disroot.org&gt;
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216785
Acked-by: Coly Li &lt;colyli@suse.de&gt;
Cc: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20230106060229.never.047-kees@kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper</title>
<updated>2023-01-05T23:48:45+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2022-09-26T21:43:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b942a520d9e43bc31f0808d2f2267a1ddba75518'/>
<id>b942a520d9e43bc31f0808d2f2267a1ddba75518</id>
<content type='text'>
Zero-length arrays are deprecated and we are moving towards adopting
C99 flexible-array members, instead. So, replace zero-length arrays
declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
helper macro.

This helper allows for flexible-array members in unions.

Link: https://github.com/KSPP/linux/issues/193
Link: https://github.com/KSPP/linux/issues/213
Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Zero-length arrays are deprecated and we are moving towards adopting
C99 flexible-array members, instead. So, replace zero-length arrays
declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
helper macro.

This helper allows for flexible-array members in unions.

Link: https://github.com/KSPP/linux/issues/193
Link: https://github.com/KSPP/linux/issues/213
Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux</title>
<updated>2022-12-13T18:43:59+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-12-13T18:43:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ce8a79d5601aab94c02ed4539c48e8605422ac94'/>
<id>ce8a79d5601aab94c02ed4539c48e8605422ac94</id>
<content type='text'>
Pull block updates from Jens Axboe:

 - NVMe pull requests via Christoph:
      - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan
        Joshi)
      - Refactor PCIe probing and reset (Christoph Hellwig)
      - Various fabrics authentication fixes and improvements (Sagi
        Grimberg)
      - Avoid fallback to sequential scan due to transient issues (Uday
        Shankar)
      - Implement support for the DEAC bit in Write Zeroes (Christoph
        Hellwig)
      - Allow overriding the IEEE OUI and firmware revision in configfs
        for nvmet (Aleksandr Miloserdov)
      - Force reconnect when number of queue changes in nvmet (Daniel
        Wagner)
      - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi
        Grimberg, Christoph Hellwig, Christophe JAILLET)
      - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni)
      - Use the common tagset helpers in nvme-pci driver (Christoph
        Hellwig)
      - Cleanup the nvme-pci removal path (Christoph Hellwig)
      - Use kstrtobool() instead of strtobool (Christophe JAILLET)
      - Allow unprivileged passthrough of Identify Controller (Joel
        Granados)
      - Support io stats on the mpath device (Sagi Grimberg)
      - Minor nvmet cleanup (Sagi Grimberg)

 - MD pull requests via Song:
      - Code cleanups (Christoph)
      - Various fixes

 - Floppy pull request from Denis:
      - Fix a memory leak in the init error path (Yuan)

 - Series fixing some batch wakeup issues with sbitmap (Gabriel)

 - Removal of the pktcdvd driver that was deprecated more than 5 years
   ago, and subsequent removal of the devnode callback in struct
   block_device_operations as no users are now left (Greg)

 - Fix for partition read on an exclusively opened bdev (Jan)

 - Series of elevator API cleanups (Jinlong, Christoph)

 - Series of fixes and cleanups for blk-iocost (Kemeng)

 - Series of fixes and cleanups for blk-throttle (Kemeng)

 - Series adding concurrent support for sync queues in BFQ (Yu)

 - Series bringing drbd a bit closer to the out-of-tree maintained
   version (Christian, Joel, Lars, Philipp)

 - Misc drbd fixes (Wang)

 - blk-wbt fixes and tweaks for enable/disable (Yu)

 - Fixes for mq-deadline for zoned devices (Damien)

 - Add support for read-only and offline zones for null_blk
   (Shin'ichiro)

 - Series fixing the delayed holder tracking, as used by DM (Yu,
   Christoph)

 - Series enabling bio alloc caching for IRQ based IO (Pavel)

 - Series enabling userspace peer-to-peer DMA (Logan)

 - BFQ waker fixes (Khazhismel)

 - Series fixing elevator refcount issues (Christoph, Jinlong)

 - Series cleaning up references around queue destruction (Christoph)

 - Series doing quiesce by tagset, enabling cleanups in drivers
   (Christoph, Chao)

 - Series untangling the queue kobject and queue references (Christoph)

 - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye,
   Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph)

* tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits)
  blktrace: Fix output non-blktrace event when blk_classic option enabled
  block: sed-opal: Don't include &lt;linux/kernel.h&gt;
  sed-opal: allow using IOC_OPAL_SAVE for locking too
  blk-cgroup: Fix typo in comment
  block: remove bio_set_op_attrs
  nvmet: don't open-code NVME_NS_ATTR_RO enumeration
  nvme-pci: use the tagset alloc/free helpers
  nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set
  nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers
  nvme: consolidate setting the tagset flags
  nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set
  block: bio_copy_data_iter
  nvme-pci: split out a nvme_pci_ctrl_is_dead helper
  nvme-pci: return early on ctrl state mismatch in nvme_reset_work
  nvme-pci: rename nvme_disable_io_queues
  nvme-pci: cleanup nvme_suspend_queue
  nvme-pci: remove nvme_pci_disable
  nvme-pci: remove nvme_disable_admin_queue
  nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl
  nvme: use nvme_wait_ready in nvme_shutdown_ctrl
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull block updates from Jens Axboe:

 - NVMe pull requests via Christoph:
      - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan
        Joshi)
      - Refactor PCIe probing and reset (Christoph Hellwig)
      - Various fabrics authentication fixes and improvements (Sagi
        Grimberg)
      - Avoid fallback to sequential scan due to transient issues (Uday
        Shankar)
      - Implement support for the DEAC bit in Write Zeroes (Christoph
        Hellwig)
      - Allow overriding the IEEE OUI and firmware revision in configfs
        for nvmet (Aleksandr Miloserdov)
      - Force reconnect when number of queue changes in nvmet (Daniel
        Wagner)
      - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi
        Grimberg, Christoph Hellwig, Christophe JAILLET)
      - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni)
      - Use the common tagset helpers in nvme-pci driver (Christoph
        Hellwig)
      - Cleanup the nvme-pci removal path (Christoph Hellwig)
      - Use kstrtobool() instead of strtobool (Christophe JAILLET)
      - Allow unprivileged passthrough of Identify Controller (Joel
        Granados)
      - Support io stats on the mpath device (Sagi Grimberg)
      - Minor nvmet cleanup (Sagi Grimberg)

 - MD pull requests via Song:
      - Code cleanups (Christoph)
      - Various fixes

 - Floppy pull request from Denis:
      - Fix a memory leak in the init error path (Yuan)

 - Series fixing some batch wakeup issues with sbitmap (Gabriel)

 - Removal of the pktcdvd driver that was deprecated more than 5 years
   ago, and subsequent removal of the devnode callback in struct
   block_device_operations as no users are now left (Greg)

 - Fix for partition read on an exclusively opened bdev (Jan)

 - Series of elevator API cleanups (Jinlong, Christoph)

 - Series of fixes and cleanups for blk-iocost (Kemeng)

 - Series of fixes and cleanups for blk-throttle (Kemeng)

 - Series adding concurrent support for sync queues in BFQ (Yu)

 - Series bringing drbd a bit closer to the out-of-tree maintained
   version (Christian, Joel, Lars, Philipp)

 - Misc drbd fixes (Wang)

 - blk-wbt fixes and tweaks for enable/disable (Yu)

 - Fixes for mq-deadline for zoned devices (Damien)

 - Add support for read-only and offline zones for null_blk
   (Shin'ichiro)

 - Series fixing the delayed holder tracking, as used by DM (Yu,
   Christoph)

 - Series enabling bio alloc caching for IRQ based IO (Pavel)

 - Series enabling userspace peer-to-peer DMA (Logan)

 - BFQ waker fixes (Khazhismel)

 - Series fixing elevator refcount issues (Christoph, Jinlong)

 - Series cleaning up references around queue destruction (Christoph)

 - Series doing quiesce by tagset, enabling cleanups in drivers
   (Christoph, Chao)

 - Series untangling the queue kobject and queue references (Christoph)

 - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye,
   Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph)

* tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits)
  blktrace: Fix output non-blktrace event when blk_classic option enabled
  block: sed-opal: Don't include &lt;linux/kernel.h&gt;
  sed-opal: allow using IOC_OPAL_SAVE for locking too
  blk-cgroup: Fix typo in comment
  block: remove bio_set_op_attrs
  nvmet: don't open-code NVME_NS_ATTR_RO enumeration
  nvme-pci: use the tagset alloc/free helpers
  nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set
  nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers
  nvme: consolidate setting the tagset flags
  nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set
  block: bio_copy_data_iter
  nvme-pci: split out a nvme_pci_ctrl_is_dead helper
  nvme-pci: return early on ctrl state mismatch in nvme_reset_work
  nvme-pci: rename nvme_disable_io_queues
  nvme-pci: cleanup nvme_suspend_queue
  nvme-pci: remove nvme_pci_disable
  nvme-pci: remove nvme_disable_admin_queue
  nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl
  nvme: use nvme_wait_ready in nvme_shutdown_ctrl
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>block: remove bio_set_op_attrs</title>
<updated>2022-12-07T16:43:12+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2022-12-06T14:40:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c34b7ac65087554627f4840f4ecd6f2107a68fd1'/>
<id>c34b7ac65087554627f4840f4ecd6f2107a68fd1</id>
<content type='text'>
This macro is obsolete, so replace the last few uses with open coded
bi_opf assignments.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Coly Li &lt;colyli@suse.de &lt;mailto:colyli@suse.de&gt;&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Link: https://lore.kernel.org/r/20221206144057.720846-1-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>
This macro is obsolete, so replace the last few uses with open coded
bi_opf assignments.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Coly Li &lt;colyli@suse.de &lt;mailto:colyli@suse.de&gt;&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Link: https://lore.kernel.org/r/20221206144057.720846-1-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: use get_random_u32_below() instead of deprecated function</title>
<updated>2022-11-18T01:15:15+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-10T02:44:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8032bf1233a74627ce69b803608e650f3f35971c'/>
<id>8032bf1233a74627ce69b803608e650f3f35971c</id>
<content type='text'>
This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
  (E)

Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Reviewed-by: SeongJae Park &lt;sj@kernel.org&gt; # for damon
Reviewed-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt; # for infiniband
Reviewed-by: Russell King (Oracle) &lt;rmk+kernel@armlinux.org.uk&gt; # for arm
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
  (E)

Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Reviewed-by: SeongJae Park &lt;sj@kernel.org&gt; # for damon
Reviewed-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt; # for infiniband
Reviewed-by: Russell King (Oracle) &lt;rmk+kernel@armlinux.org.uk&gt; # for arm
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: use prandom_u32_max() when possible, part 1</title>
<updated>2022-10-11T23:42:55+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T14:43:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=81895a65ec63ee1daec3255dc1a06675d2fbe915'/>
<id>81895a65ec63ee1daec3255dc1a06675d2fbe915</id>
<content type='text'>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: fix set_at_max_writeback_rate() for multiple attached devices</title>
<updated>2022-09-19T17:12:35+00:00</updated>
<author>
<name>Coly Li</name>
<email>colyli@suse.de</email>
</author>
<published>2022-09-19T16:16:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d2d05b88035d2d51a5bb6c5afec88a0880c73df4'/>
<id>d2d05b88035d2d51a5bb6c5afec88a0880c73df4</id>
<content type='text'>
Inside set_at_max_writeback_rate() the calculation in following if()
check is wrong,
	if (atomic_inc_return(&amp;c-&gt;idle_counter) &lt;
	    atomic_read(&amp;c-&gt;attached_dev_nr) * 6)

Because each attached backing device has its own writeback thread
running and increasing c-&gt;idle_counter, the counter increates much
faster than expected. The correct calculation should be,
	(counter / dev_nr) &lt; dev_nr * 6
which equals to,
	counter &lt; dev_nr * dev_nr * 6

This patch fixes the above mistake with correct calculation, and helper
routine idle_counter_exceeded() is added to make code be more clear.

Reported-by: Mingzhe Zou &lt;mingzhe.zou@easystack.cn&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Acked-by: Mingzhe Zou &lt;mingzhe.zou@easystack.cn&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-6-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Inside set_at_max_writeback_rate() the calculation in following if()
check is wrong,
	if (atomic_inc_return(&amp;c-&gt;idle_counter) &lt;
	    atomic_read(&amp;c-&gt;attached_dev_nr) * 6)

Because each attached backing device has its own writeback thread
running and increasing c-&gt;idle_counter, the counter increates much
faster than expected. The correct calculation should be,
	(counter / dev_nr) &lt; dev_nr * 6
which equals to,
	counter &lt; dev_nr * dev_nr * 6

This patch fixes the above mistake with correct calculation, and helper
routine idle_counter_exceeded() is added to make code be more clear.

Reported-by: Mingzhe Zou &lt;mingzhe.zou@easystack.cn&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Acked-by: Mingzhe Zou &lt;mingzhe.zou@easystack.cn&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-6-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache:: fix repeated words in comments</title>
<updated>2022-09-19T17:12:35+00:00</updated>
<author>
<name>Jilin Yuan</name>
<email>yuanjilin@cdjrlc.com</email>
</author>
<published>2022-09-19T16:16:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6dd3be6923eec2c49860e7292e4e2783c74a9dff'/>
<id>6dd3be6923eec2c49860e7292e4e2783c74a9dff</id>
<content type='text'>
Delete the redundant word 'we'.

Signed-off-by: Jilin Yuan &lt;yuanjilin@cdjrlc.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-5-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Delete the redundant word 'we'.

Signed-off-by: Jilin Yuan &lt;yuanjilin@cdjrlc.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-5-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: bset: Fix comment typos</title>
<updated>2022-09-19T17:12:35+00:00</updated>
<author>
<name>Jules Maselbas</name>
<email>jmaselbas@kalray.eu</email>
</author>
<published>2022-09-19T16:16:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=11e529ccea33f24af6b54fe10bb3be9c1c48eddb'/>
<id>11e529ccea33f24af6b54fe10bb3be9c1c48eddb</id>
<content type='text'>
Remove the redundant word `by`, correct the typo `creaated`.

CC: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
CC: linux-bcache@vger.kernel.org
Signed-off-by: Jules Maselbas &lt;jmaselbas@kalray.eu&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-4-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Remove the redundant word `by`, correct the typo `creaated`.

CC: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
CC: linux-bcache@vger.kernel.org
Signed-off-by: Jules Maselbas &lt;jmaselbas@kalray.eu&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20220919161647.81238-4-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
</feed>
