linux-stable.git/Documentation/admin-guide, branch linux-5.6.y Linux kernel stable tree x86/speculation: Add Ivy Bridge to affected list 2020-06-10T18:22:53+00:00 Josh Poimboeuf jpoimboe@redhat.com 2020-04-27T18:46:13+00:00 1e6cd20e44d4578c39a6bffbd84638bfb4c4d73b commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream Make the docs match the code. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream

Make the docs match the code.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/speculation: Add SRBDS vulnerability and mitigation documentation 2020-06-10T18:22:52+00:00 Mark Gross mgross@linux.intel.com 2020-04-16T16:21:51+00:00 897d1639c38691742c36d4c3f3c099396b18d314 commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream Add documentation for the SRBDS vulnerability and its mitigation. [ bp: Massage. jpoimboe: sysfs table strings. ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream

Add documentation for the SRBDS vulnerability and its mitigation.

 [ bp: Massage.
   jpoimboe: sysfs table strings. ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation 2020-06-10T18:22:52+00:00 Mark Gross mgross@linux.intel.com 2020-04-16T15:54:04+00:00 49491339c97686dc697aff1b1ddcb426d62f9eff commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream

SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.

While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.

The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.

* Enable administrator to configure the mitigation off when desired using
  either mitigations=off or srbds=off.

* Export vulnerability status via sysfs

* Rename file-scoped macros to apply for non-whitelist table initializations.

 [ bp: Massage,
   - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
   - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
   - flip check in cpu_set_bug_bits() to save an indentation level,
   - reflow comments.
   jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
   tglx: Dropped the fused off magic for now
 ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: hub: Revert commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") 2020-04-29T14:34:45+00:00 Alan Stern stern@rowland.harvard.edu 2020-04-22T20:13:08+00:00 f8092b0e021762ab73656d6ec87a6c9e90aff4f4 commit 3155f4f40811c5d7e3c686215051acf504e05565 upstream. Commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") changed the way the hub driver enumerates high-speed devices. Instead of using the "new" enumeration scheme first and switching to the "old" scheme if that doesn't work, we start with the "old" scheme. In theory this is better because the "old" scheme is slightly faster -- it involves resetting the device only once instead of twice. However, for a long time Windows used only the "new" scheme. Zeng Tao said that Windows 8 and later use the "old" scheme for high-speed devices, but apparently there are some devices that don't like it. William Bader reports that the Ricoh webcam built into his Sony Vaio laptop not only doesn't enumerate under the "old" scheme, it gets hung up so badly that it won't then enumerate under the "new" scheme! Only a cold reset will fix it. Therefore we will revert the commit and go back to trying the "new" scheme first for high-speed devices. Reported-and-tested-by: William Bader <williambader@hotmail.com> Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219 Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") CC: Zeng Tao <prime.zeng@hisilicon.com> CC: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3155f4f40811c5d7e3c686215051acf504e05565 upstream.

Commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for
high speed devices") changed the way the hub driver enumerates
high-speed devices.  Instead of using the "new" enumeration scheme
first and switching to the "old" scheme if that doesn't work, we start
with the "old" scheme.  In theory this is better because the "old"
scheme is slightly faster -- it involves resetting the device only
once instead of twice.

However, for a long time Windows used only the "new" scheme.  Zeng Tao
said that Windows 8 and later use the "old" scheme for high-speed
devices, but apparently there are some devices that don't like it.
William Bader reports that the Ricoh webcam built into his Sony Vaio
laptop not only doesn't enumerate under the "old" scheme, it gets hung
up so badly that it won't then enumerate under the "new" scheme!  Only
a cold reset will fix it.

Therefore we will revert the commit and go back to trying the "new"
scheme first for high-speed devices.

Reported-and-tested-by: William Bader <williambader@hotmail.com>
Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices")
CC: Zeng Tao <prime.zeng@hisilicon.com>
CC: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
docs: Fix path to MTD command line partition parser 2020-04-23T08:38:25+00:00 Jonathan Neuschäfer j.neuschaefer@gmx.net 2020-02-18T15:02:19+00:00 93814a21a812b9ce10296a5e2be16a568d857c4d commit fb2511247dc4061fd122d0195838278a4a0b7b59 upstream. cmdlinepart.c has been moved to drivers/mtd/parsers/. Fixes: a3f12a35c91d ("mtd: parsers: Move CMDLINE parser") Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fb2511247dc4061fd122d0195838278a4a0b7b59 upstream.

cmdlinepart.c has been moved to drivers/mtd/parsers/.

Fixes: a3f12a35c91d ("mtd: parsers: Move CMDLINE parser")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
time/namespace: Add max_time_namespaces ucount 2020-04-17T14:13:36+00:00 Dmitry Safonov dima@arista.com 2020-04-06T17:13:42+00:00 b8ba50560134a1e8ec745518f2809d2ac9085878 commit eeec26d5da8248ea4e240b8795bb4364213d3247 upstream. Michael noticed that userns limit for number of time namespaces is missing. Furthermore, time namespace introduced UCOUNT_TIME_NAMESPACES, but didn't introduce an array member in user_table[]. It would make array's initialisation OOB write, but by luck the user_table array has an excessive empty member (all accesses to the array are limited with UCOUNT_COUNTS - so it silently reuses the last free member. Fixes user-visible regression: max_inotify_instances by reason of the missing UCOUNT_ENTRY() has limited max number of namespaces instead of the number of inotify instances. Fixes: 769071ac9f20 ("ns: Introduce Time Namespace") Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andrei Vagin <avagin@gmail.com> Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: stable@kernel.org Link: https://lkml.kernel.org/r/20200406171342.128733-1-dima@arista.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit eeec26d5da8248ea4e240b8795bb4364213d3247 upstream.

Michael noticed that userns limit for number of time namespaces is missing.

Furthermore, time namespace introduced UCOUNT_TIME_NAMESPACES, but didn't
introduce an array member in user_table[]. It would make array's
initialisation OOB write, but by luck the user_table array has an excessive
empty member (all accesses to the array are limited with UCOUNT_COUNTS - so
it silently reuses the last free member.

Fixes user-visible regression: max_inotify_instances by reason of the
missing UCOUNT_ENTRY() has limited max number of namespaces instead of the
number of inotify instances.

Fixes: 769071ac9f20 ("ns: Introduce Time Namespace")
Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andrei Vagin <avagin@gmail.com>
Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: stable@kernel.org
Link: https://lkml.kernel.org/r/20200406171342.128733-1-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge branch 'acpi-doc' 2020-03-06T09:57:46+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2020-03-06T09:57:46+00:00 86dfa5bec24952f99f2cfa778975d5a914c3a1d2 * acpi-doc: Documentation/admin-guide/acpi: fix fan_performance_states.rst warnings 
* acpi-doc:
  Documentation/admin-guide/acpi: fix fan_performance_states.rst warnings
Merge tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 2020-02-28T17:02:18+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-02-28T17:02:18+00:00 c60c04021353c55b133519804734415f647f08bd Pull ACPI fixes from Rafael Wysocki: "Fix a couple of configuration issues in the ACPI watchdog (WDAT) driver (Mika Westerberg) and make it possible to disable that driver at boot time in case it still does not work as expected (Jean Delvare)" * tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: watchdog: Set default timeout in probe ACPI: watchdog: Fix gas->access_width usage ACPICA: Introduce ACPI_ACCESS_BYTE_WIDTH() macro ACPI: watchdog: Allow disabling WDAT at boot 
Pull ACPI fixes from Rafael Wysocki:
 "Fix a couple of configuration issues in the ACPI watchdog (WDAT)
  driver (Mika Westerberg) and make it possible to disable that driver
  at boot time in case it still does not work as expected (Jean
  Delvare)"

* tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: watchdog: Set default timeout in probe
  ACPI: watchdog: Fix gas->access_width usage
  ACPICA: Introduce ACPI_ACCESS_BYTE_WIDTH() macro
  ACPI: watchdog: Allow disabling WDAT at boot
Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace 2020-02-26T18:34:42+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-02-26T18:34:42+00:00 91ad64a84e9e63e2906ae714dfa3933dd3f64c64 Pull tracing and bootconfig updates: "Fixes and changes to bootconfig before it goes live in a release. Change in API of bootconfig (before it comes live in a release): - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists - Set CONFIG_BOOT_CONFIG to 'n' by default - Show error if "bootconfig" on cmdline but not compiled in - Prevent redefining the same value - Have a way to append values - Added a SELECT BLK_DEV_INITRD to fix a build failure Synthetic event fixes: - Switch to raw_smp_processor_id() for recording CPU value in preempt section. (No care for what the value actually is) - Fix samples always recording u64 values - Fix endianess - Check number of values matches number of fields - Fix a printing bug Fix of trace_printk() breaking postponed start up tests Make a function static that is only used in a single file" * tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue bootconfig: Add append value operator support bootconfig: Prohibit re-defining value on same key bootconfig: Print array as multiple commands for legacy command line bootconfig: Reject subkey and value on same parent key tools/bootconfig: Remove unneeded error message silencer bootconfig: Add bootconfig magic word for indicating bootconfig explicitly bootconfig: Set CONFIG_BOOT_CONFIG=n by default tracing: Clear trace_state when starting trace bootconfig: Mark boot_config_checksum() static tracing: Disable trace_printk() on post poned tests tracing: Have synthetic event test use raw_smp_processor_id() tracing: Fix number printing bug in print_synth_event() tracing: Check that number of vals matches number of synth event fields tracing: Make synth_event trace functions endian-correct tracing: Make sure synth_event_trace() example always uses u64 
Pull tracing and bootconfig updates:
 "Fixes and changes to bootconfig before it goes live in a release.

  Change in API of bootconfig (before it comes live in a release):
  - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
    exists
  - Set CONFIG_BOOT_CONFIG to 'n' by default
  - Show error if "bootconfig" on cmdline but not compiled in
  - Prevent redefining the same value
  - Have a way to append values
  - Added a SELECT BLK_DEV_INITRD to fix a build failure

  Synthetic event fixes:
  - Switch to raw_smp_processor_id() for recording CPU value in preempt
    section. (No care for what the value actually is)
  - Fix samples always recording u64 values
  - Fix endianess
  - Check number of values matches number of fields
  - Fix a printing bug

  Fix of trace_printk() breaking postponed start up tests

  Make a function static that is only used in a single file"

* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
  bootconfig: Add append value operator support
  bootconfig: Prohibit re-defining value on same key
  bootconfig: Print array as multiple commands for legacy command line
  bootconfig: Reject subkey and value on same parent key
  tools/bootconfig: Remove unneeded error message silencer
  bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
  bootconfig: Set CONFIG_BOOT_CONFIG=n by default
  tracing: Clear trace_state when starting trace
  bootconfig: Mark boot_config_checksum() static
  tracing: Disable trace_printk() on post poned tests
  tracing: Have synthetic event test use raw_smp_processor_id()
  tracing: Fix number printing bug in print_synth_event()
  tracing: Check that number of vals matches number of synth event fields
  tracing: Make synth_event trace functions endian-correct
  tracing: Make sure synth_event_trace() example always uses u64
bootconfig: Add append value operator support 2020-02-21T14:59:39+00:00 Masami Hiramatsu mhiramat@kernel.org 2020-02-21T08:13:52+00:00 5f811c57c99205e048926293bb812c750a6ea562 Add append value operator "+=" support to bootconfig syntax. With this operator, user can add new value to the key as an entry of array instead of overwriting. For example, foo = bar ... foo += baz Then the key "foo" has "bar" and "baz" values as an array. Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> 
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,

  foo = bar
  ...
  foo += baz

Then the key "foo" has "bar" and "baz" values as an array.

Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>