<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/lib, branch v5.0-rc7</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'compiler-attributes-for-linus-v5.0-rc7' of git://github.com/ojeda/linux</title>
<updated>2019-02-16T18:28:05+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-02-16T18:28:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0b999ae3614d09d97a1575936bcee884f912b10e'/>
<id>0b999ae3614d09d97a1575936bcee884f912b10e</id>
<content type='text'>
Pull compiler attributes fixes from Miguel Ojeda:
 "Clean the new GCC 9 -Wmissing-attributes warnings

  The upcoming GCC 9 release extends the -Wmissing-attributes warnings
  (enabled by -Wall) to C and aliases: it warns when particular function
  attributes are missing in the aliases but not in their target, e.g.:

    void __cold f(void) {}
    void __alias("f") g(void);

  diagnoses:

    warning: 'g' specifies less restrictive attribute than
    its target 'f': 'cold' [-Wmissing-attributes]

  These patch series clean these new warnings. Most of them are caused
  by the module_init/exit macros"

Link: https://lore.kernel.org/lkml/20190125104353.2791-1-labbott@redhat.com/

* tag 'compiler-attributes-for-linus-v5.0-rc7' of git://github.com/ojeda/linux:
  include/linux/module.h: copy __init/__exit attrs to init/cleanup_module
  Compiler Attributes: add support for __copy (gcc &gt;= 9)
  lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull compiler attributes fixes from Miguel Ojeda:
 "Clean the new GCC 9 -Wmissing-attributes warnings

  The upcoming GCC 9 release extends the -Wmissing-attributes warnings
  (enabled by -Wall) to C and aliases: it warns when particular function
  attributes are missing in the aliases but not in their target, e.g.:

    void __cold f(void) {}
    void __alias("f") g(void);

  diagnoses:

    warning: 'g' specifies less restrictive attribute than
    its target 'f': 'cold' [-Wmissing-attributes]

  These patch series clean these new warnings. Most of them are caused
  by the module_init/exit macros"

Link: https://lore.kernel.org/lkml/20190125104353.2791-1-labbott@redhat.com/

* tag 'compiler-attributes-for-linus-v5.0-rc7' of git://github.com/ojeda/linux:
  include/linux/module.h: copy __init/__exit attrs to init/cleanup_module
  Compiler Attributes: add support for __copy (gcc &gt;= 9)
  lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure</title>
<updated>2019-02-15T18:50:07+00:00</updated>
<author>
<name>Miguel Ojeda</name>
<email>miguel.ojeda.sandonis@gmail.com</email>
</author>
<published>2019-01-24T14:59:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ff98e20ef2081b8620dada28fc2d4fb24ca0abf2'/>
<id>ff98e20ef2081b8620dada28fc2d4fb24ca0abf2</id>
<content type='text'>
The upcoming GCC 9 release extends the -Wmissing-attributes warnings
(enabled by -Wall) to C and aliases: it warns when particular function
attributes are missing in the aliases but not in their target.

In particular, it triggers here because crc32_le_base/__crc32c_le_base
aren't __pure while their target crc32_le/__crc32c_le are.

These aliases are used by architectures as a fallback in accelerated
versions of CRC32. See commit 9784d82db3eb ("lib/crc32: make core crc32()
routines weak so they can be overridden").

Therefore, being fallbacks, it is likely that even if the aliases
were called from C, there wouldn't be any optimizations possible.
Currently, the only user is arm64, which calls this from asm.

Still, marking the aliases as __pure makes sense and is a good idea
for documentation purposes and possible future optimizations,
which also silences the warning.

Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Tested-by: Laura Abbott &lt;labbott@redhat.com&gt;
Signed-off-by: Miguel Ojeda &lt;miguel.ojeda.sandonis@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The upcoming GCC 9 release extends the -Wmissing-attributes warnings
(enabled by -Wall) to C and aliases: it warns when particular function
attributes are missing in the aliases but not in their target.

In particular, it triggers here because crc32_le_base/__crc32c_le_base
aren't __pure while their target crc32_le/__crc32c_le are.

These aliases are used by architectures as a fallback in accelerated
versions of CRC32. See commit 9784d82db3eb ("lib/crc32: make core crc32()
routines weak so they can be overridden").

Therefore, being fallbacks, it is likely that even if the aliases
were called from C, there wouldn't be any optimizations possible.
Currently, the only user is arm64, which calls this from asm.

Still, marking the aliases as __pure makes sense and is a good idea
for documentation purposes and possible future optimizations,
which also silences the warning.

Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Tested-by: Laura Abbott &lt;labbott@redhat.com&gt;
Signed-off-by: Miguel Ojeda &lt;miguel.ojeda.sandonis@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2019-02-08T19:21:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-02-08T19:21:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=27b4ad621e887ce8e5eb508a0103f13d30f6b38a'/>
<id>27b4ad621e887ce8e5eb508a0103f13d30f6b38a</id>
<content type='text'>
Pull networking fixes from David Miller:
 "This pull request is dedicated to the upcoming snowpocalypse parts 2
  and 3 in the Pacific Northwest:

   1) Drop profiles are broken because some drivers use dev_kfree_skb*
      instead of dev_consume_skb*, from Yang Wei.

   2) Fix IWLWIFI kconfig deps, from Luca Coelho.

   3) Fix percpu maps updating in bpftool, from Paolo Abeni.

   4) Missing station release in batman-adv, from Felix Fietkau.

   5) Fix some networking compat ioctl bugs, from Johannes Berg.

   6) ucc_geth must reset the BQL queue state when stopping the device,
      from Mathias Thore.

   7) Several XDP bug fixes in virtio_net from Toshiaki Makita.

   8) TSO packets must be sent always on queue 0 in stmmac, from Jose
      Abreu.

   9) Fix socket refcounting bug in RDS, from Eric Dumazet.

  10) Handle sparse cpu allocations in bpf selftests, from Martynas
      Pumputis.

  11) Make sure mgmt frames have enough tailroom in mac80211, from Felix
      Feitkau.

  12) Use safe list walking in sctp_sendmsg() asoc list traversal, from
      Greg Kroah-Hartman.

  13) Make DCCP's ccid_hc_[rt]x_parse_options always check for NULL
      ccid, from Eric Dumazet.

  14) Need to reload WoL password into bcmsysport device after deep
      sleeps, from Florian Fainelli.

  15) Remove filter from mask before freeing in cls_flower, from Petr
      Machata.

  16) Missing release and use after free in error paths of s390 qeth
      code, from Julian Wiedmann.

  17) Fix lockdep false positive in dsa code, from Marc Zyngier.

  18) Fix counting of ATU violations in mv88e6xxx, from Andrew Lunn.

  19) Fix EQ firmware assert in qed driver, from Manish Chopra.

  20) Don't default Caivum PTP to Y in kconfig, from Bjorn Helgaas"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  net: dsa: b53: Fix for failure when irq is not defined in dt
  sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
  geneve: should not call rt6_lookup() when ipv6 was disabled
  net: Don't default Cavium PTP driver to 'y'
  net: broadcom: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: via-velocity: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tehuti: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: sun: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fsl_ucc_hdlc: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fec_mpc52xx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: smsc: epic100: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: dscc4: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tulip: de2104x: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: defxx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net/mlx5e: Don't overwrite pedit action when multiple pedit used
  net/mlx5e: Update hw flows when encap source mac changed
  qed*: Advance drivers version to 8.37.0.20
  qed: Change verbosity for coalescing message.
  qede: Fix system crash on configuring channels.
  qed: Consider TX tcs while deriving the max num_queues for PF.
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from David Miller:
 "This pull request is dedicated to the upcoming snowpocalypse parts 2
  and 3 in the Pacific Northwest:

   1) Drop profiles are broken because some drivers use dev_kfree_skb*
      instead of dev_consume_skb*, from Yang Wei.

   2) Fix IWLWIFI kconfig deps, from Luca Coelho.

   3) Fix percpu maps updating in bpftool, from Paolo Abeni.

   4) Missing station release in batman-adv, from Felix Fietkau.

   5) Fix some networking compat ioctl bugs, from Johannes Berg.

   6) ucc_geth must reset the BQL queue state when stopping the device,
      from Mathias Thore.

   7) Several XDP bug fixes in virtio_net from Toshiaki Makita.

   8) TSO packets must be sent always on queue 0 in stmmac, from Jose
      Abreu.

   9) Fix socket refcounting bug in RDS, from Eric Dumazet.

  10) Handle sparse cpu allocations in bpf selftests, from Martynas
      Pumputis.

  11) Make sure mgmt frames have enough tailroom in mac80211, from Felix
      Feitkau.

  12) Use safe list walking in sctp_sendmsg() asoc list traversal, from
      Greg Kroah-Hartman.

  13) Make DCCP's ccid_hc_[rt]x_parse_options always check for NULL
      ccid, from Eric Dumazet.

  14) Need to reload WoL password into bcmsysport device after deep
      sleeps, from Florian Fainelli.

  15) Remove filter from mask before freeing in cls_flower, from Petr
      Machata.

  16) Missing release and use after free in error paths of s390 qeth
      code, from Julian Wiedmann.

  17) Fix lockdep false positive in dsa code, from Marc Zyngier.

  18) Fix counting of ATU violations in mv88e6xxx, from Andrew Lunn.

  19) Fix EQ firmware assert in qed driver, from Manish Chopra.

  20) Don't default Caivum PTP to Y in kconfig, from Bjorn Helgaas"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  net: dsa: b53: Fix for failure when irq is not defined in dt
  sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
  geneve: should not call rt6_lookup() when ipv6 was disabled
  net: Don't default Cavium PTP driver to 'y'
  net: broadcom: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: via-velocity: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tehuti: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: sun: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fsl_ucc_hdlc: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fec_mpc52xx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: smsc: epic100: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: dscc4: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tulip: de2104x: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: defxx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net/mlx5e: Don't overwrite pedit action when multiple pedit used
  net/mlx5e: Update hw flows when encap source mac changed
  qed*: Advance drivers version to 8.37.0.20
  qed: Change verbosity for coalescing message.
  qede: Fix system crash on configuring channels.
  qed: Consider TX tcs while deriving the max num_queues for PF.
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/test_kmod.c: potential double free in error handling</title>
<updated>2019-02-01T23:46:23+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2019-02-01T22:20:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=db7ddeab3ce5d64c9696e70d61f45ea9909cd196'/>
<id>db7ddeab3ce5d64c9696e70d61f45ea9909cd196</id>
<content type='text'>
There is a copy and paste bug so we set "config-&gt;test_driver" to NULL
twice instead of setting "config-&gt;test_fs".  Smatch complains that it
leads to a double free:

  lib/test_kmod.c:840 __kmod_config_init() warn: 'config-&gt;test_fs' double freed

Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Acked-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is a copy and paste bug so we set "config-&gt;test_driver" to NULL
twice instead of setting "config-&gt;test_fs".  Smatch complains that it
leads to a double free:

  lib/test_kmod.c:840 __kmod_config_init() warn: 'config-&gt;test_fs' double freed

Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Acked-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/test_rhashtable: Make test_insert_dup() allocate its hash table dynamically</title>
<updated>2019-01-31T17:36:52+00:00</updated>
<author>
<name>Bart Van Assche</name>
<email>bvanassche@acm.org</email>
</author>
<published>2019-01-30T18:42:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fc42a689c4c097859e5bd37b5ea11b60dc426df6'/>
<id>fc42a689c4c097859e5bd37b5ea11b60dc426df6</id>
<content type='text'>
The test_insert_dup() function from lib/test_rhashtable.c passes a
pointer to a stack object to rhltable_init(). Allocate the hash table
dynamically to avoid that the following is reported with object
debugging enabled:

ODEBUG: object (ptrval) is on stack (ptrval), but NOT annotated.
WARNING: CPU: 0 PID: 1 at lib/debugobjects.c:368 __debug_object_init+0x312/0x480
Modules linked in:
EIP: __debug_object_init+0x312/0x480
Call Trace:
 ? debug_object_init+0x1a/0x20
 ? __init_work+0x16/0x30
 ? rhashtable_init+0x1e1/0x460
 ? sched_clock_cpu+0x57/0xe0
 ? rhltable_init+0xb/0x20
 ? test_insert_dup+0x32/0x20f
 ? trace_hardirqs_on+0x38/0xf0
 ? ida_dump+0x10/0x10
 ? jhash+0x130/0x130
 ? my_hashfn+0x30/0x30
 ? test_rht_init+0x6aa/0xab4
 ? ida_dump+0x10/0x10
 ? test_rhltable+0xc5c/0xc5c
 ? do_one_initcall+0x67/0x28e
 ? trace_hardirqs_off+0x22/0xe0
 ? restore_all_kernel+0xf/0x70
 ? trace_hardirqs_on_thunk+0xc/0x10
 ? restore_all_kernel+0xf/0x70
 ? kernel_init_freeable+0x142/0x213
 ? rest_init+0x230/0x230
 ? kernel_init+0x10/0x110
 ? schedule_tail_wrapper+0x9/0xc
 ? ret_from_fork+0x19/0x24

Cc: Thomas Graf &lt;tgraf@suug.ch&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The test_insert_dup() function from lib/test_rhashtable.c passes a
pointer to a stack object to rhltable_init(). Allocate the hash table
dynamically to avoid that the following is reported with object
debugging enabled:

ODEBUG: object (ptrval) is on stack (ptrval), but NOT annotated.
WARNING: CPU: 0 PID: 1 at lib/debugobjects.c:368 __debug_object_init+0x312/0x480
Modules linked in:
EIP: __debug_object_init+0x312/0x480
Call Trace:
 ? debug_object_init+0x1a/0x20
 ? __init_work+0x16/0x30
 ? rhashtable_init+0x1e1/0x460
 ? sched_clock_cpu+0x57/0xe0
 ? rhltable_init+0xb/0x20
 ? test_insert_dup+0x32/0x20f
 ? trace_hardirqs_on+0x38/0xf0
 ? ida_dump+0x10/0x10
 ? jhash+0x130/0x130
 ? my_hashfn+0x30/0x30
 ? test_rht_init+0x6aa/0xab4
 ? ida_dump+0x10/0x10
 ? test_rhltable+0xc5c/0xc5c
 ? do_one_initcall+0x67/0x28e
 ? trace_hardirqs_off+0x22/0xe0
 ? restore_all_kernel+0xf/0x70
 ? trace_hardirqs_on_thunk+0xc/0x10
 ? restore_all_kernel+0xf/0x70
 ? kernel_init_freeable+0x142/0x213
 ? rest_init+0x230/0x230
 ? kernel_init+0x10/0x110
 ? schedule_tail_wrapper+0x9/0xc
 ? ret_from_fork+0x19/0x24

Cc: Thomas Graf &lt;tgraf@suug.ch&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'xarray-5.0-rc3' of git://git.infradead.org/users/willy/linux-dax</title>
<updated>2019-01-22T04:08:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-01-22T04:08:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=48b161983ae5266ffa42f0ccaf7224eaeda38e59'/>
<id>48b161983ae5266ffa42f0ccaf7224eaeda38e59</id>
<content type='text'>
Pull XArray fixes from Matthew Wilcox:
 "Fix some oversights in the XArray porcelain API:

   - support for m68k's two-byte aligned pointers

   - reserving entries using xa_insert()

   - missing xa_insert_bh() and xa_insert_irq() functions

   - simplify using xa_for_each()

   - use lockdep correctly

   - a few other minor fixes and improvements"

* tag 'xarray-5.0-rc3' of git://git.infradead.org/users/willy/linux-dax:
  XArray: Fix an arithmetic error in xa_is_err
  XArray tests: Check mark 2 gets squashed
  XArray: Fix typo in comment
  XArray: Honour reserved entries in xa_insert
  XArray: Permit storing 2-byte-aligned pointers
  XArray: Change xa_for_each iterator
  XArray: Turn xa_init_flags into a static inline
  XArray tests: Add RCU locking
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull XArray fixes from Matthew Wilcox:
 "Fix some oversights in the XArray porcelain API:

   - support for m68k's two-byte aligned pointers

   - reserving entries using xa_insert()

   - missing xa_insert_bh() and xa_insert_irq() functions

   - simplify using xa_for_each()

   - use lockdep correctly

   - a few other minor fixes and improvements"

* tag 'xarray-5.0-rc3' of git://git.infradead.org/users/willy/linux-dax:
  XArray: Fix an arithmetic error in xa_is_err
  XArray tests: Check mark 2 gets squashed
  XArray: Fix typo in comment
  XArray: Honour reserved entries in xa_insert
  XArray: Permit storing 2-byte-aligned pointers
  XArray: Change xa_for_each iterator
  XArray: Turn xa_init_flags into a static inline
  XArray tests: Add RCU locking
</pre>
</div>
</content>
</entry>
<entry>
<title>fix int_sqrt64() for very large numbers</title>
<updated>2019-01-20T18:20:18+00:00</updated>
<author>
<name>Florian La Roche</name>
<email>florian.laroche@googlemail.com</email>
</author>
<published>2019-01-19T15:14:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fbfaf851902cd9293f392f3a1735e0543016d530'/>
<id>fbfaf851902cd9293f392f3a1735e0543016d530</id>
<content type='text'>
If an input number x for int_sqrt64() has the highest bit set, then
fls64(x) is 64.  (1UL &lt;&lt; 64) is an overflow and breaks the algorithm.

Subtracting 1 is a better guess for the initial value of m anyway and
that's what also done in int_sqrt() implicitly [*].

[*] Note how int_sqrt() uses __fls() with two underscores, which already
    returns the proper raw bit number.

    In contrast, int_sqrt64() used fls64(), and that returns bit numbers
    illogically starting at 1, because of error handling for the "no
    bits set" case. Will points out that he bug probably is due to a
    copy-and-paste error from the regular int_sqrt() case.

Signed-off-by: Florian La Roche &lt;Florian.LaRoche@googlemail.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If an input number x for int_sqrt64() has the highest bit set, then
fls64(x) is 64.  (1UL &lt;&lt; 64) is an overflow and breaks the algorithm.

Subtracting 1 is a better guess for the initial value of m anyway and
that's what also done in int_sqrt() implicitly [*].

[*] Note how int_sqrt() uses __fls() with two underscores, which already
    returns the proper raw bit number.

    In contrast, int_sqrt64() used fls64(), and that returns bit numbers
    illogically starting at 1, because of error handling for the "no
    bits set" case. Will points out that he bug probably is due to a
    copy-and-paste error from the regular int_sqrt() case.

Signed-off-by: Florian La Roche &lt;Florian.LaRoche@googlemail.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sbitmap: Protect swap_lock from hardirq</title>
<updated>2019-01-15T04:29:57+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@redhat.com</email>
</author>
<published>2019-01-15T03:59:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fe76fc6aaf538df27708ffa3e5d549a6c8e16142'/>
<id>fe76fc6aaf538df27708ffa3e5d549a6c8e16142</id>
<content type='text'>
Because we may call blk_mq_get_driver_tag() directly from
blk_mq_dispatch_rq_list() without holding any lock, then HARDIRQ may
come and the above DEADLOCK is triggered.

Commit ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq") tries to
fix this issue by using 'spin_lock_bh', which isn't enough because we
complete request from hardirq context direclty in case of multiqueue.

Cc: Clark Williams &lt;williams@redhat.com&gt;
Fixes: ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq")
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Because we may call blk_mq_get_driver_tag() directly from
blk_mq_dispatch_rq_list() without holding any lock, then HARDIRQ may
come and the above DEADLOCK is triggered.

Commit ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq") tries to
fix this issue by using 'spin_lock_bh', which isn't enough because we
complete request from hardirq context direclty in case of multiqueue.

Cc: Clark Williams &lt;williams@redhat.com&gt;
Fixes: ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq")
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>XArray tests: Check mark 2 gets squashed</title>
<updated>2019-01-14T19:50:34+00:00</updated>
<author>
<name>Matthew Wilcox</name>
<email>willy@infradead.org</email>
</author>
<published>2019-01-14T18:57:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d69d287a9002b70bdbe2975660b97241ccefc071'/>
<id>d69d287a9002b70bdbe2975660b97241ccefc071</id>
<content type='text'>
We do not currently check that the loop in xas_squash_marks() doesn't have
an off-by-one error in it.  It didn't, but a patch which introduced an
off-by-one error wasn't caught by any existing test.  Switch the roles
of XA_MARK_1 and XA_MARK_2 to catch that bug.

Reported-by: Cyrill Gorcunov &lt;gorcunov@gmail.com&gt;
Signed-off-by: Matthew Wilcox &lt;willy@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We do not currently check that the loop in xas_squash_marks() doesn't have
an off-by-one error in it.  It didn't, but a patch which introduced an
off-by-one error wasn't caught by any existing test.  Switch the roles
of XA_MARK_1 and XA_MARK_2 to catch that bug.

Reported-by: Cyrill Gorcunov &lt;gorcunov@gmail.com&gt;
Signed-off-by: Matthew Wilcox &lt;willy@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sbitmap: Protect swap_lock from softirqs</title>
<updated>2019-01-14T19:31:18+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2019-01-14T17:25:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3719876809e745b9db5293d418600c194bbf5c23'/>
<id>3719876809e745b9db5293d418600c194bbf5c23</id>
<content type='text'>
The swap_lock used by sbitmap has a chain with locks taken from softirq,
but the swap_lock is not protected from being preempted by softirqs.

A chain exists of:

 sbq-&gt;ws[i].wait -&gt; dispatch_wait_lock -&gt; swap_lock

Where the sbq-&gt;ws[i].wait lock can be taken from softirq context, which
means all locks below it in the chain must also be protected from
softirqs.

Reported-by: Clark Williams &lt;williams@redhat.com&gt;
Fixes: 58ab5e32e6fd ("sbitmap: silence bogus lockdep IRQ warning")
Fixes: ea86ea2cdced ("sbitmap: amortize cost of clearing bits")
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The swap_lock used by sbitmap has a chain with locks taken from softirq,
but the swap_lock is not protected from being preempted by softirqs.

A chain exists of:

 sbq-&gt;ws[i].wait -&gt; dispatch_wait_lock -&gt; swap_lock

Where the sbq-&gt;ws[i].wait lock can be taken from softirq context, which
means all locks below it in the chain must also be protected from
softirqs.

Reported-by: Clark Williams &lt;williams@redhat.com&gt;
Fixes: 58ab5e32e6fd ("sbitmap: silence bogus lockdep IRQ warning")
Fixes: ea86ea2cdced ("sbitmap: amortize cost of clearing bits")
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
