<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git, branch v5.14-rc4</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Linux 5.14-rc4</title>
<updated>2021-08-02T00:04:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-08-02T00:04:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c500bee1c5b2f1d59b1081ac879d73268ab0ff17'/>
<id>c500bee1c5b2f1d59b1081ac879d73268ab0ff17</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux</title>
<updated>2021-08-01T19:25:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-08-01T19:25:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d4affd6b6e81443ec8d00de0306ca61911e81441'/>
<id>d4affd6b6e81443ec8d00de0306ca61911e81441</id>
<content type='text'>
Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Revert "perf map: Fix dso-&gt;nsinfo refcounting", this makes 'perf top'
   abort, uncovering a design flaw on how namespace information is kept.
   The fix for that is more than we can do right now, leave it for the
   next merge window.

 - Split --dump-raw-trace by AUX records for ARM's CoreSight, fixing up
   the decoding of some records.

 - Fix PMU alias matching.

Thanks to James Clark and John Garry for these fixes.

* tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  Revert "perf map: Fix dso-&gt;nsinfo refcounting"
  perf pmu: Fix alias matching
  perf cs-etm: Split --dump-raw-trace by AUX records
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Revert "perf map: Fix dso-&gt;nsinfo refcounting", this makes 'perf top'
   abort, uncovering a design flaw on how namespace information is kept.
   The fix for that is more than we can do right now, leave it for the
   next merge window.

 - Split --dump-raw-trace by AUX records for ARM's CoreSight, fixing up
   the decoding of some records.

 - Fix PMU alias matching.

Thanks to James Clark and John Garry for these fixes.

* tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  Revert "perf map: Fix dso-&gt;nsinfo refcounting"
  perf pmu: Fix alias matching
  perf cs-etm: Split --dump-raw-trace by AUX records
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2021-08-01T19:18:44+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-08-01T19:18:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c82357a7b32c0690b8581f72f197b1ce6118543c'/>
<id>c82357a7b32c0690b8581f72f197b1ce6118543c</id>
<content type='text'>
Pull powerpc fixes from Michael Ellerman:

 - Don't use r30 in VDSO code, to avoid breaking existing Go lang
   programs.

 - Change an export symbol to allow non-GPL modules to use spinlocks
   again.

Thanks to Paul Menzel, and Srikar Dronamraju.

* tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/vdso: Don't use r30 to avoid breaking Go lang
  powerpc/pseries: Fix regression while building external modules
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc fixes from Michael Ellerman:

 - Don't use r30 in VDSO code, to avoid breaking existing Go lang
   programs.

 - Change an export symbol to allow non-GPL modules to use spinlocks
   again.

Thanks to Paul Menzel, and Srikar Dronamraju.

* tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/vdso: Don't use r30 to avoid breaking Go lang
  powerpc/pseries: Fix regression while building external modules
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux</title>
<updated>2021-08-01T19:07:23+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-08-01T19:07:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=aa6603266cc0760ebb83cf11cb5a2b8fca84cd68'/>
<id>aa6603266cc0760ebb83cf11cb5a2b8fca84cd68</id>
<content type='text'>
Pull xfs fixes from Darrick Wong:
 "This contains a bunch of bug fixes in XFS.

  Dave and I have been busy the last couple of weeks to find and fix as
  many log recovery bugs as we can find; here are the results so far. Go
  fstests -g recoveryloop! ;)

   - Fix a number of coordination bugs relating to cache flushes for
     metadata writeback, cache flushes for multi-buffer log writes, and
     FUA writes for single-buffer log writes

   - Fix a bug with incorrect replay of attr3 blocks

   - Fix unnecessary stalls when flushing logs to disk

   - Fix spoofing problems when recovering realtime bitmap blocks"

* tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: prevent spoofing of rtbitmap blocks when recovering buffers
  xfs: limit iclog tail updates
  xfs: need to see iclog flags in tracing
  xfs: Enforce attr3 buffer recovery order
  xfs: logging the on disk inode LSN can make it go backwards
  xfs: avoid unnecessary waits in xfs_log_force_lsn()
  xfs: log forces imply data device cache flushes
  xfs: factor out forced iclog flushes
  xfs: fix ordering violation between cache flushes and tail updates
  xfs: fold __xlog_state_release_iclog into xlog_state_release_iclog
  xfs: external logs need to flush data device
  xfs: flush data dev on external log write
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull xfs fixes from Darrick Wong:
 "This contains a bunch of bug fixes in XFS.

  Dave and I have been busy the last couple of weeks to find and fix as
  many log recovery bugs as we can find; here are the results so far. Go
  fstests -g recoveryloop! ;)

   - Fix a number of coordination bugs relating to cache flushes for
     metadata writeback, cache flushes for multi-buffer log writes, and
     FUA writes for single-buffer log writes

   - Fix a bug with incorrect replay of attr3 blocks

   - Fix unnecessary stalls when flushing logs to disk

   - Fix spoofing problems when recovering realtime bitmap blocks"

* tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: prevent spoofing of rtbitmap blocks when recovering buffers
  xfs: limit iclog tail updates
  xfs: need to see iclog flags in tracing
  xfs: Enforce attr3 buffer recovery order
  xfs: logging the on disk inode LSN can make it go backwards
  xfs: avoid unnecessary waits in xfs_log_force_lsn()
  xfs: log forces imply data device cache flushes
  xfs: factor out forced iclog flushes
  xfs: fix ordering violation between cache flushes and tail updates
  xfs: fold __xlog_state_release_iclog into xlog_state_release_iclog
  xfs: external logs need to flush data device
  xfs: flush data dev on external log write
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6</title>
<updated>2021-07-31T16:25:12+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-31T16:25:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f3438b4c4e692b49b7dc2bab864d20381024be16'/>
<id>f3438b4c4e692b49b7dc2bab864d20381024be16</id>
<content type='text'>
Pull cifs fixes from Steve French:
 "Three cifs/smb3 fixes, including two for stable, and a fix for an
  fallocate problem noticed by Clang"

* tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: add missing parsing of backupuid
  smb3: rc uninitialized in one fallocate path
  SMB3: fix readpage for large swap cache
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull cifs fixes from Steve French:
 "Three cifs/smb3 fixes, including two for stable, and a fix for an
  fallocate problem noticed by Clang"

* tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: add missing parsing of backupuid
  smb3: rc uninitialized in one fallocate path
  SMB3: fix readpage for large swap cache
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2021-07-30T23:01:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-30T23:01:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c7d102232649226a69dddd58a4942cf13cff4f7c'/>
<id>c7d102232649226a69dddd58a4942cf13cff4f7c</id>
<content type='text'>
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.14-rc4, including fixes from bpf, can, WiFi
  (mac80211) and netfilter trees.

  Current release - regressions:

   - mac80211: fix starting aggregation sessions on mesh interfaces

  Current release - new code bugs:

   - sctp: send pmtu probe only if packet loss in Search Complete state

   - bnxt_en: add missing periodic PHC overflow check

   - devlink: fix phys_port_name of virtual port and merge error

   - hns3: change the method of obtaining default ptp cycle

   - can: mcba_usb_start(): add missing urb-&gt;transfer_dma initialization

  Previous releases - regressions:

   - set true network header for ECN decapsulation

   - mlx5e: RX, avoid possible data corruption w/ relaxed ordering and
     LRO

   - phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811
     PHY

   - sctp: fix return value check in __sctp_rcv_asconf_lookup

  Previous releases - always broken:

   - bpf:
       - more spectre corner case fixes, introduce a BPF nospec
         instruction for mitigating Spectre v4
       - fix OOB read when printing XDP link fdinfo
       - sockmap: fix cleanup related races

   - mac80211: fix enabling 4-address mode on a sta vif after assoc

   - can:
       - raw: raw_setsockopt(): fix raw_rcv panic for sock UAF
       - j1939: j1939_session_deactivate(): clarify lifetime of session
         object, avoid UAF
       - fix number of identical memory leaks in USB drivers

   - tipc:
       - do not blindly write skb_shinfo frags when doing decryption
       - fix sleeping in tipc accept routine"

* tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
  gve: Update MAINTAINERS list
  can: esd_usb2: fix memory leak
  can: ems_usb: fix memory leak
  can: usb_8dev: fix memory leak
  can: mcba_usb_start(): add missing urb-&gt;transfer_dma initialization
  can: hi311x: fix a signedness bug in hi3110_cmd()
  MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver
  bpf: Fix leakage due to insufficient speculative store bypass mitigation
  bpf: Introduce BPF nospec instruction for mitigating Spectre v4
  sis900: Fix missing pci_disable_device() in probe and remove
  net: let flow have same hash in two directions
  nfc: nfcsim: fix use after free during module unload
  tulip: windbond-840: Fix missing pci_disable_device() in probe and remove
  sctp: fix return value check in __sctp_rcv_asconf_lookup
  nfc: s3fwrn5: fix undefined parameter values in dev_err()
  net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32
  net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev()
  net/mlx5: Unload device upon firmware fatal error
  net/mlx5e: Fix page allocation failure for ptp-RQ over SF
  net/mlx5e: Fix page allocation failure for trap-RQ over SF
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.14-rc4, including fixes from bpf, can, WiFi
  (mac80211) and netfilter trees.

  Current release - regressions:

   - mac80211: fix starting aggregation sessions on mesh interfaces

  Current release - new code bugs:

   - sctp: send pmtu probe only if packet loss in Search Complete state

   - bnxt_en: add missing periodic PHC overflow check

   - devlink: fix phys_port_name of virtual port and merge error

   - hns3: change the method of obtaining default ptp cycle

   - can: mcba_usb_start(): add missing urb-&gt;transfer_dma initialization

  Previous releases - regressions:

   - set true network header for ECN decapsulation

   - mlx5e: RX, avoid possible data corruption w/ relaxed ordering and
     LRO

   - phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811
     PHY

   - sctp: fix return value check in __sctp_rcv_asconf_lookup

  Previous releases - always broken:

   - bpf:
       - more spectre corner case fixes, introduce a BPF nospec
         instruction for mitigating Spectre v4
       - fix OOB read when printing XDP link fdinfo
       - sockmap: fix cleanup related races

   - mac80211: fix enabling 4-address mode on a sta vif after assoc

   - can:
       - raw: raw_setsockopt(): fix raw_rcv panic for sock UAF
       - j1939: j1939_session_deactivate(): clarify lifetime of session
         object, avoid UAF
       - fix number of identical memory leaks in USB drivers

   - tipc:
       - do not blindly write skb_shinfo frags when doing decryption
       - fix sleeping in tipc accept routine"

* tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
  gve: Update MAINTAINERS list
  can: esd_usb2: fix memory leak
  can: ems_usb: fix memory leak
  can: usb_8dev: fix memory leak
  can: mcba_usb_start(): add missing urb-&gt;transfer_dma initialization
  can: hi311x: fix a signedness bug in hi3110_cmd()
  MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver
  bpf: Fix leakage due to insufficient speculative store bypass mitigation
  bpf: Introduce BPF nospec instruction for mitigating Spectre v4
  sis900: Fix missing pci_disable_device() in probe and remove
  net: let flow have same hash in two directions
  nfc: nfcsim: fix use after free during module unload
  tulip: windbond-840: Fix missing pci_disable_device() in probe and remove
  sctp: fix return value check in __sctp_rcv_asconf_lookup
  nfc: s3fwrn5: fix undefined parameter values in dev_err()
  net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32
  net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev()
  net/mlx5: Unload device upon firmware fatal error
  net/mlx5e: Fix page allocation failure for ptp-RQ over SF
  net/mlx5e: Fix page allocation failure for trap-RQ over SF
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'acpi-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2021-07-30T22:56:24+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-30T22:56:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e1dab4c02de0b495a9393915d71e452f8e77a464'/>
<id>e1dab4c02de0b495a9393915d71e452f8e77a464</id>
<content type='text'>
Pull ACPI fixes from Rafael Wysocki:
 "These revert a recent IRQ resources handling modification that turned
  out to be problematic, fix suspend-to-idle handling on AMD platforms
  to take upcoming systems into account properly and fix the retrieval
  of the DPTF attributes of the PCH FIVR.

  Specifics:

   - Revert recent change of the ACPI IRQ resources handling that
     attempted to improve the ACPI IRQ override selection logic, but
     introduced serious regressions on some systems (Hui Wang).

   - Fix up quirks for AMD platforms in the suspend-to-idle support code
     so as to take upcoming systems using uPEP HID AMDI007 into account
     as appropriate (Mario Limonciello).

   - Fix the code retrieving DPTF attributes of the PCH FIVR so that it
     agrees on the return data type with the ACPI control method
     evaluated for this purpose (Srinivas Pandruvada)"

* tag 'acpi-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: DPTF: Fix reading of attributes
  Revert "ACPI: resources: Add checks for ACPI IRQ override"
  ACPI: PM: Add support for upcoming AMD uPEP HID AMDI007
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ACPI fixes from Rafael Wysocki:
 "These revert a recent IRQ resources handling modification that turned
  out to be problematic, fix suspend-to-idle handling on AMD platforms
  to take upcoming systems into account properly and fix the retrieval
  of the DPTF attributes of the PCH FIVR.

  Specifics:

   - Revert recent change of the ACPI IRQ resources handling that
     attempted to improve the ACPI IRQ override selection logic, but
     introduced serious regressions on some systems (Hui Wang).

   - Fix up quirks for AMD platforms in the suspend-to-idle support code
     so as to take upcoming systems using uPEP HID AMDI007 into account
     as appropriate (Mario Limonciello).

   - Fix the code retrieving DPTF attributes of the PCH FIVR so that it
     agrees on the return data type with the ACPI control method
     evaluated for this purpose (Srinivas Pandruvada)"

* tag 'acpi-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: DPTF: Fix reading of attributes
  Revert "ACPI: resources: Add checks for ACPI IRQ override"
  ACPI: PM: Add support for upcoming AMD uPEP HID AMDI007
</pre>
</div>
</content>
</entry>
<entry>
<title>pipe: make pipe writes always wake up readers</title>
<updated>2021-07-30T22:42:34+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-30T22:42:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3a34b13a88caeb2800ab44a4918f230041b37dd9'/>
<id>3a34b13a88caeb2800ab44a4918f230041b37dd9</id>
<content type='text'>
Since commit 1b6b26ae7053 ("pipe: fix and clarify pipe write wakeup
logic") we have sanitized the pipe write logic, and would only try to
wake up readers if they needed it.

In particular, if the pipe already had data in it before the write,
there was no point in trying to wake up a reader, since any existing
readers must have been aware of the pre-existing data already.  Doing
extraneous wakeups will only cause potential thundering herd problems.

However, it turns out that some Android libraries have misused the EPOLL
interface, and expected "edge triggered" be to "any new write will
trigger it".  Even if there was no edge in sight.

Quoting Sandeep Patil:
 "The commit 1b6b26ae7053 ('pipe: fix and clarify pipe write wakeup
  logic') changed pipe write logic to wakeup readers only if the pipe
  was empty at the time of write. However, there are libraries that
  relied upon the older behavior for notification scheme similar to
  what's described in [1]

  One such library 'realm-core'[2] is used by numerous Android
  applications. The library uses a similar notification mechanism as GNU
  Make but it never drains the pipe until it is full. When Android moved
  to v5.10 kernel, all applications using this library stopped working.

  The library has since been fixed[3] but it will be a while before all
  applications incorporate the updated library"

Our regression rule for the kernel is that if applications break from
new behavior, it's a regression, even if it was because the application
did something patently wrong.  Also note the original report [4] by
Michal Kerrisk about a test for this epoll behavior - but at that point
we didn't know of any actual broken use case.

So add the extraneous wakeup, to approximate the old behavior.

[ I say "approximate", because the exact old behavior was to do a wakeup
  not for each write(), but for each pipe buffer chunk that was filled
  in. The behavior introduced by this change is not that - this is just
  "every write will cause a wakeup, whether necessary or not", which
  seems to be sufficient for the broken library use. ]

It's worth noting that this adds the extraneous wakeup only for the
write side, while the read side still considers the "edge" to be purely
about reading enough from the pipe to allow further writes.

See commit f467a6a66419 ("pipe: fix and clarify pipe read wakeup logic")
for the pipe read case, which remains that "only wake up if the pipe was
full, and we read something from it".

Link: https://lore.kernel.org/lkml/CAHk-=wjeG0q1vgzu4iJhW5juPkTsjTYmiqiMUYAebWW+0bam6w@mail.gmail.com/ [1]
Link: https://github.com/realm/realm-core [2]
Link: https://github.com/realm/realm-core/issues/4666 [3]
Link: https://lore.kernel.org/lkml/CAKgNAkjMBGeAwF=2MKK758BhxvW58wYTgYKB2V-gY1PwXxrH+Q@mail.gmail.com/ [4]
Link: https://lore.kernel.org/lkml/20210729222635.2937453-1-sspatil@android.com/
Reported-by: Sandeep Patil &lt;sspatil@android.com&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.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>
Since commit 1b6b26ae7053 ("pipe: fix and clarify pipe write wakeup
logic") we have sanitized the pipe write logic, and would only try to
wake up readers if they needed it.

In particular, if the pipe already had data in it before the write,
there was no point in trying to wake up a reader, since any existing
readers must have been aware of the pre-existing data already.  Doing
extraneous wakeups will only cause potential thundering herd problems.

However, it turns out that some Android libraries have misused the EPOLL
interface, and expected "edge triggered" be to "any new write will
trigger it".  Even if there was no edge in sight.

Quoting Sandeep Patil:
 "The commit 1b6b26ae7053 ('pipe: fix and clarify pipe write wakeup
  logic') changed pipe write logic to wakeup readers only if the pipe
  was empty at the time of write. However, there are libraries that
  relied upon the older behavior for notification scheme similar to
  what's described in [1]

  One such library 'realm-core'[2] is used by numerous Android
  applications. The library uses a similar notification mechanism as GNU
  Make but it never drains the pipe until it is full. When Android moved
  to v5.10 kernel, all applications using this library stopped working.

  The library has since been fixed[3] but it will be a while before all
  applications incorporate the updated library"

Our regression rule for the kernel is that if applications break from
new behavior, it's a regression, even if it was because the application
did something patently wrong.  Also note the original report [4] by
Michal Kerrisk about a test for this epoll behavior - but at that point
we didn't know of any actual broken use case.

So add the extraneous wakeup, to approximate the old behavior.

[ I say "approximate", because the exact old behavior was to do a wakeup
  not for each write(), but for each pipe buffer chunk that was filled
  in. The behavior introduced by this change is not that - this is just
  "every write will cause a wakeup, whether necessary or not", which
  seems to be sufficient for the broken library use. ]

It's worth noting that this adds the extraneous wakeup only for the
write side, while the read side still considers the "edge" to be purely
about reading enough from the pipe to allow further writes.

See commit f467a6a66419 ("pipe: fix and clarify pipe read wakeup logic")
for the pipe read case, which remains that "only wake up if the pipe was
full, and we read something from it".

Link: https://lore.kernel.org/lkml/CAHk-=wjeG0q1vgzu4iJhW5juPkTsjTYmiqiMUYAebWW+0bam6w@mail.gmail.com/ [1]
Link: https://github.com/realm/realm-core [2]
Link: https://github.com/realm/realm-core/issues/4666 [3]
Link: https://lore.kernel.org/lkml/CAKgNAkjMBGeAwF=2MKK758BhxvW58wYTgYKB2V-gY1PwXxrH+Q@mail.gmail.com/ [4]
Link: https://lore.kernel.org/lkml/20210729222635.2937453-1-sspatil@android.com/
Reported-by: Sandeep Patil &lt;sspatil@android.com&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "perf map: Fix dso-&gt;nsinfo refcounting"</title>
<updated>2021-07-30T21:26:22+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-07-30T21:26:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9bac1bd6e6d36459087a728a968e79e37ebcea1a'/>
<id>9bac1bd6e6d36459087a728a968e79e37ebcea1a</id>
<content type='text'>
This makes 'perf top' abort in some cases, and the right fix will
involve surgery that is too much to do at this stage, so revert for now
and fix it in the next merge window.

This reverts commit 2d6b74baa7147251c30a46c4996e8cc224aa2dc5.

Cc: Riccardo Mancini &lt;rickyman7@gmail.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Krister Johansen &lt;kjlx@templeofstupid.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This makes 'perf top' abort in some cases, and the right fix will
involve surgery that is too much to do at this stage, so revert for now
and fix it in the next merge window.

This reverts commit 2d6b74baa7147251c30a46c4996e8cc224aa2dc5.

Cc: Riccardo Mancini &lt;rickyman7@gmail.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Krister Johansen &lt;kjlx@templeofstupid.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'acpi-resources' and 'acpi-dptf'</title>
<updated>2021-07-30T18:26:38+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-07-30T18:26:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e83f54eacf137de228a52c20c74e77f575684600'/>
<id>e83f54eacf137de228a52c20c74e77f575684600</id>
<content type='text'>
* acpi-resources:
  Revert "ACPI: resources: Add checks for ACPI IRQ override"

* acpi-dptf:
  ACPI: DPTF: Fix reading of attributes
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* acpi-resources:
  Revert "ACPI: resources: Add checks for ACPI IRQ override"

* acpi-dptf:
  ACPI: DPTF: Fix reading of attributes
</pre>
</div>
</content>
</entry>
</feed>
