linux-stable.git/Documentation/admin-guide, branch linux-5.9.y Linux kernel stable tree USB: UAS: introduce a quirk to set no_write_same 2020-12-21T12:28:20+00:00 Oliver Neukum oneukum@suse.com 2020-12-09T15:26:39+00:00 4848b8000a284b1abc908b818f052987a21a498a commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream. UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk. Add it to the device that needs it. Reported-by: David C. Partridge <david.partridge@perdrix.co.uk> Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream.

UAS does not share the pessimistic assumption storage is making that
devices cannot deal with WRITE_SAME.  A few devices supported by UAS,
are reported to not deal well with WRITE_SAME. Those need a quirk.

Add it to the device that needs it.

Reported-by: David C. Partridge <david.partridge@perdrix.co.uk>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/64s: flush L1D after user accesses 2020-11-22T09:15:32+00:00 Nicholas Piggin npiggin@gmail.com 2020-11-19T23:22:48+00:00 ab13e7fce101aabea634b4087bfc0f4a131e8bff commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream.

IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern. This patch flushes the L1 cache after user accesses.

This is part of the fix for CVE-2020-4788.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/64s: flush L1D on kernel entry 2020-11-22T09:15:32+00:00 Nicholas Piggin npiggin@gmail.com 2020-11-19T23:22:47+00:00 e590b36718d6e740b7b19514f710402a6499164c commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream.

IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern. This patch flushes the L1 cache on kernel entry.

This is part of the fix for CVE-2020-4788.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xen/events: defer eoi in case of excessive number of events 2020-11-05T10:51:08+00:00 Juergen Gross jgross@suse.com 2020-09-07T13:47:30+00:00 d985af1ca3d0e07c3167c712a0288450aa14a002 commit e99502f76271d6bc4e374fe368c50c67a1fd3070 upstream. In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e99502f76271d6bc4e374fe368c50c67a1fd3070 upstream.

In case rogue guests are sending events at high frequency it might
happen that xen_evtchn_do_upcall() won't stop processing events in
dom0. As this is done in irq handling a crash might be the result.

In order to avoid that, delay further inter-domain events after some
time in xen_evtchn_do_upcall() by forcing eoi processing into a
worker on the same cpu, thus inhibiting new events coming in.

The time after which eoi processing is to be delayed is configurable
via a new module parameter "event_loop_timeout" which specifies the
maximum event loop time in jiffies (default: 2, the value was chosen
after some tests showing that a value of 2 was the lowest with an
only slight drop of dom0 network throughput while multiple guests
performed an event storm).

How long eoi processing will be delayed can be specified via another
parameter "event_eoi_delay" (again in jiffies, default 10, again the
value was chosen after testing with different delay values).

This is part of XSA-332.

Cc: stable@vger.kernel.org
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Wei Liu <wl@xen.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/fpu: Allow multiple bits in clearcpuid= parameter 2020-10-29T09:11:00+00:00 Arvind Sankar nivedita@alum.mit.edu 2020-09-07T21:39:19+00:00 928c35799946b2917f6b64a3c88f6e7dcae59dfa [ Upstream commit 0a4bb5e5507a585532cc413125b921c8546fc39f ] Commit 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") changed clearcpuid parsing from __setup() to cmdline_find_option(). While the __setup() function would have been called for each clearcpuid= parameter on the command line, cmdline_find_option() will only return the last one, so the change effectively made it impossible to disable more than one bit. Allow a comma-separated list of bit numbers as the argument for clearcpuid to allow multiple bits to be disabled again. Log the bits being disabled for informational purposes. Also fix the check on the return value of cmdline_find_option(). It returns -1 when the option is not found, so testing as a boolean is incorrect. Fixes: 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200907213919.2423441-1-nivedita@alum.mit.edu Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0a4bb5e5507a585532cc413125b921c8546fc39f ]

Commit

  0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument")

changed clearcpuid parsing from __setup() to cmdline_find_option().
While the __setup() function would have been called for each clearcpuid=
parameter on the command line, cmdline_find_option() will only return
the last one, so the change effectively made it impossible to disable
more than one bit.

Allow a comma-separated list of bit numbers as the argument for
clearcpuid to allow multiple bits to be disabled again. Log the bits
being disabled for informational purposes.

Also fix the check on the return value of cmdline_find_option(). It
returns -1 when the option is not found, so testing as a boolean is
incorrect.

Fixes: 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907213919.2423441-1-nivedita@alum.mit.edu
Signed-off-by: Sasha Levin <sashal@kernel.org>
Documentation: PM: Fix a reStructuredText syntax error 2020-09-30T15:40:37+00:00 Yoann Congal yoann.congal@smile.fr 2020-09-29T20:41:58+00:00 eac53b3e304a8354dc2a2f38e60e712d0e110ef6 Fix a reStructuredText syntax error in the cpuidle PM admin-guide documentation: the ``...'' quotation marks are parsed as partial ''...'' reStructuredText markup and break the output formatting. This change them to "...". Signed-off-by: Yoann Congal <yoann.congal@smile.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Fix a reStructuredText syntax error in the cpuidle PM admin-guide
documentation: the ``...'' quotation marks are parsed as partial ''...''
reStructuredText markup and break the output formatting.

This change them to "...".

Signed-off-by: Yoann Congal <yoann.congal@smile.fr>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
mm: memcontrol: fix missing suffix of workingset_restore 2020-09-26T17:33:57+00:00 Muchun Song songmuchun@bytedance.com 2020-09-26T04:19:05+00:00 8d3fe09d8d6645dcbbe2413cde58f51ceb6545a6 We forget to add the suffix to the workingset_restore string, so fix it. And also update the documentation of cgroup-v2.rst. Fixes: 170b04b7ae49 ("mm/workingset: prepare the workingset detection infrastructure for anon LRU") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Randy Dunlap <rdunlap@infradead.org> Link: https://lkml.kernel.org/r/20200916100030.71698-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
We forget to add the suffix to the workingset_restore string, so fix it.

And also update the documentation of cgroup-v2.rst.

Fixes: 170b04b7ae49 ("mm/workingset: prepare the workingset detection infrastructure for anon LRU")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/20200916100030.71698-1-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dm crypt: document encrypted keyring key option 2020-09-22T17:25:58+00:00 Milan Broz gmazyland@gmail.com 2020-08-20T19:20:26+00:00 4c07ae0ad493b7b2d3dd3e53870e594f136ce8a5 Commit 27f5411a718c4 ("dm crypt: support using encrypted keys") introduced support for encrypted keyring type. Fix documentation in admin guide to mention this type. Fixes: 27f5411a718c4 ("dm crypt: support using encrypted keys") Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> 
Commit 27f5411a718c4 ("dm crypt: support using encrypted keys")
introduced support for encrypted keyring type.

Fix documentation in admin guide to mention this type.

Fixes: 27f5411a718c4 ("dm crypt: support using encrypted keys")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm crypt: document new no_workqueue flags 2020-09-22T17:24:46+00:00 Milan Broz gmazyland@gmail.com 2020-08-20T17:45:38+00:00 4a5caa4af0df5cd8f1c7f0c2f871d382662b022e Commit 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd workqueues") introduced new dm-crypt 'no_read_workqueue' and 'no_write_workqueue' flags. Add documentation to admin guide for them. Fixes: 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd workqueues") Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> 
Commit 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd
workqueues") introduced new dm-crypt 'no_read_workqueue' and
'no_write_workqueue' flags.

Add documentation to admin guide for them.

Fixes: 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd workqueues")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Merge tag 'char-misc-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc 2020-09-13T15:52:21+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-09-13T15:52:21+00:00 2a1a4bee5ef277c7dc2906d9268db61478876288 Pull char / misc driver fixes from Greg KH: "Here are a number of small driver fixes for 5.9-rc5 Included in here are: - habanalabs driver fixes - interconnect driver fixes - soundwire driver fixes - dyndbg fixes for reported issues, and then reverts to fix it all up to a sane state. - phy driver fixes All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: Revert "dyndbg: accept query terms like file=bar and module=foo" Revert "dyndbg: fix problem parsing format="foo bar"" scripts/tags.sh: exclude tools directory from tags generation video: fbdev: fix OOB read in vga_8planes_imageblit() dyndbg: fix problem parsing format="foo bar" dyndbg: refine export, rename to dynamic_debug_exec_queries() dyndbg: give %3u width in pr-format, cosmetic only interconnect: qcom: Fix small BW votes being truncated to zero soundwire: fix double free of dangling pointer interconnect: Show bandwidth for disabled paths as zero in debugfs habanalabs: fix report of RAZWI initiator coordinates habanalabs: prevent user buff overflow phy: omap-usb2-phy: disable PHY charger detect phy: qcom-qmp: Use correct values for ipq8074 PCIe Gen2 PHY init soundwire: bus: fix typo in comment on INTSTAT registers phy: qualcomm: fix return value check in qcom_ipq806x_usb_phy_probe() phy: qualcomm: fix platform_no_drv_owner.cocci warnings 
Pull char / misc driver fixes from Greg KH:
 "Here are a number of small driver fixes for 5.9-rc5

  Included in here are:

   - habanalabs driver fixes

   - interconnect driver fixes

   - soundwire driver fixes

   - dyndbg fixes for reported issues, and then reverts to fix it all up
     to a sane state.

   - phy driver fixes

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Revert "dyndbg: accept query terms like file=bar and module=foo"
  Revert "dyndbg: fix problem parsing format="foo bar""
  scripts/tags.sh: exclude tools directory from tags generation
  video: fbdev: fix OOB read in vga_8planes_imageblit()
  dyndbg: fix problem parsing format="foo bar"
  dyndbg: refine export, rename to dynamic_debug_exec_queries()
  dyndbg: give %3u width in pr-format, cosmetic only
  interconnect: qcom: Fix small BW votes being truncated to zero
  soundwire: fix double free of dangling pointer
  interconnect: Show bandwidth for disabled paths as zero in debugfs
  habanalabs: fix report of RAZWI initiator coordinates
  habanalabs: prevent user buff overflow
  phy: omap-usb2-phy: disable PHY charger detect
  phy: qcom-qmp: Use correct values for ipq8074 PCIe Gen2 PHY init
  soundwire: bus: fix typo in comment on INTSTAT registers
  phy: qualcomm: fix return value check in qcom_ipq806x_usb_phy_probe()
  phy: qualcomm: fix platform_no_drv_owner.cocci warnings