<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/Documentation, branch v4.14.151</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>arm64/speculation: Support 'mitigations=' cmdline option</title>
<updated>2019-10-29T08:17:30+00:00</updated>
<author>
<name>Josh Poimboeuf</name>
<email>jpoimboe@redhat.com</email>
</author>
<published>2019-10-24T12:48:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5fff7a398c266c8c202a24e573327ba2c1566524'/>
<id>5fff7a398c266c8c202a24e573327ba2c1566524</id>
<content type='text'>
[ Upstream commit a111b7c0f20e13b54df2fa959b3dc0bdf1925ae6 ]

Configure arm64 runtime CPU speculation bug mitigations in accordance
with the 'mitigations=' cmdline option.  This affects Meltdown, Spectre
v2, and Speculative Store Bypass.

The default behavior is unchanged.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
[will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a111b7c0f20e13b54df2fa959b3dc0bdf1925ae6 ]

Configure arm64 runtime CPU speculation bug mitigations in accordance
with the 'mitigations=' cmdline option.  This affects Meltdown, Spectre
v2, and Speculative Store Bypass.

The default behavior is unchanged.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
[will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Provide a command line to disable spectre_v2 mitigation</title>
<updated>2019-10-29T08:17:27+00:00</updated>
<author>
<name>Jeremy Linton</name>
<email>jeremy.linton@arm.com</email>
</author>
<published>2019-10-24T12:48:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=02fd5d7f6d027912901a68d671c0449295966cd7'/>
<id>02fd5d7f6d027912901a68d671c0449295966cd7</id>
<content type='text'>
[ Upstream commit e5ce5e7267ddcbe13ab9ead2542524e1b7993e5a ]

There are various reasons, such as benchmarking, to disable spectrev2
mitigation on a machine. Provide a command-line option to do so.

Signed-off-by: Jeremy Linton &lt;jeremy.linton@arm.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Reviewed-by: Andre Przywara &lt;andre.przywara@arm.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Tested-by: Stefan Wahren &lt;stefan.wahren@i2se.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: linux-doc@vger.kernel.org
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e5ce5e7267ddcbe13ab9ead2542524e1b7993e5a ]

There are various reasons, such as benchmarking, to disable spectrev2
mitigation on a machine. Provide a command-line option to do so.

Signed-off-by: Jeremy Linton &lt;jeremy.linton@arm.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Reviewed-by: Andre Przywara &lt;andre.przywara@arm.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Tested-by: Stefan Wahren &lt;stefan.wahren@i2se.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: linux-doc@vger.kernel.org
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Expose Arm v8.4 features</title>
<updated>2019-10-29T08:17:10+00:00</updated>
<author>
<name>Suzuki K Poulose</name>
<email>suzuki.poulose@arm.com</email>
</author>
<published>2019-10-24T12:47:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=053cdffad3dd5e4a9330433ba2b400956f33bd2b'/>
<id>053cdffad3dd5e4a9330433ba2b400956f33bd2b</id>
<content type='text'>
[ Upstream commit 7206dc93a58fb76421c4411eefa3c003337bcb2d ]

Expose the new features introduced by Arm v8.4 extensions to
Arm v8-A profile.

These include :

 1) Data indpendent timing of instructions. (DIT, exposed as HWCAP_DIT)
 2) Unaligned atomic instructions and Single-copy atomicity of loads
    and stores. (AT, expose as HWCAP_USCAT)
 3) LDAPR and STLR instructions with immediate offsets (extension to
    LRCPC, exposed as HWCAP_ILRCPC)
 4) Flag manipulation instructions (TS, exposed as HWCAP_FLAGM).

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Dave Martin &lt;dave.martin@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
[ardb: fix up context for missing SVE]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7206dc93a58fb76421c4411eefa3c003337bcb2d ]

Expose the new features introduced by Arm v8.4 extensions to
Arm v8-A profile.

These include :

 1) Data indpendent timing of instructions. (DIT, exposed as HWCAP_DIT)
 2) Unaligned atomic instructions and Single-copy atomicity of loads
    and stores. (AT, expose as HWCAP_USCAT)
 3) LDAPR and STLR instructions with immediate offsets (extension to
    LRCPC, exposed as HWCAP_ILRCPC)
 4) Flag manipulation instructions (TS, exposed as HWCAP_FLAGM).

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Dave Martin &lt;dave.martin@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
[ardb: fix up context for missing SVE]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Documentation: cpu-feature-registers: Remove RES0 fields</title>
<updated>2019-10-29T08:17:09+00:00</updated>
<author>
<name>Suzuki K Poulose</name>
<email>suzuki.poulose@arm.com</email>
</author>
<published>2019-10-24T12:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eb952c6bce53b5389c41ffc3698594cb43b5aeb9'/>
<id>eb952c6bce53b5389c41ffc3698594cb43b5aeb9</id>
<content type='text'>
[ Upstream commit 847ecd3fa311cde0f10a1b66c572abb136742b1d ]

Remove the invisible RES0 field entries from the table, listing
fields in CPU ID feature registers, as :
 1) We are only interested in the user visible fields.
 2) The field description may not be up-to-date, as the
    field could be assigned a new meaning.
 3) We already explain the rules of the fields which are not
    visible.

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Dave Martin &lt;dave.martin@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
[ardb: fix up for missing SVE in context]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 847ecd3fa311cde0f10a1b66c572abb136742b1d ]

Remove the invisible RES0 field entries from the table, listing
fields in CPU ID feature registers, as :
 1) We are only interested in the user visible fields.
 2) The field description may not be up-to-date, as the
    field could be assigned a new meaning.
 3) We already explain the rules of the fields which are not
    visible.

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Dave Martin &lt;dave.martin@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
[ardb: fix up for missing SVE in context]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: v8.4: Support for new floating point multiplication instructions</title>
<updated>2019-10-29T08:17:09+00:00</updated>
<author>
<name>Dongjiu Geng</name>
<email>gengdongjiu@huawei.com</email>
</author>
<published>2019-10-24T12:47:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1caa4f72dfc4a0401ec7fad210cfb0ed73d06b4d'/>
<id>1caa4f72dfc4a0401ec7fad210cfb0ed73d06b4d</id>
<content type='text'>
[ Upstream commit 3b3b681097fae73b7f5dcdd42db6cfdf32943d4c ]

ARM v8.4 extensions add new neon instructions for performing a
multiplication of each FP16 element of one vector with the corresponding
FP16 element of a second vector, and to add or subtract this without an
intermediate rounding to the corresponding FP32 element in a third vector.

This patch detects this feature and let the userspace know about it via a
HWCAP bit and MRS emulation.

Cc: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Dongjiu Geng &lt;gengdongjiu@huawei.com&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
[ardb: fix up for missing SVE in context]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 3b3b681097fae73b7f5dcdd42db6cfdf32943d4c ]

ARM v8.4 extensions add new neon instructions for performing a
multiplication of each FP16 element of one vector with the corresponding
FP16 element of a second vector, and to add or subtract this without an
intermediate rounding to the corresponding FP32 element in a third vector.

This patch detects this feature and let the userspace know about it via a
HWCAP bit and MRS emulation.

Cc: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Dongjiu Geng &lt;gengdongjiu@huawei.com&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
[ardb: fix up for missing SVE in context]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Expose support for optional ARMv8-A features</title>
<updated>2019-10-29T08:17:08+00:00</updated>
<author>
<name>Suzuki K Poulose</name>
<email>suzuki.poulose@arm.com</email>
</author>
<published>2019-10-24T12:47:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5f005c7e4d37213a76a1d64ed558fe7e1ff138b6'/>
<id>5f005c7e4d37213a76a1d64ed558fe7e1ff138b6</id>
<content type='text'>
[ Upstream commit f5e035f8694c3bdddc66ea46ecda965ee6853718 ]

ARMv8-A adds a few optional features for ARMv8.2 and ARMv8.3.
Expose them to the userspace via HWCAPs and mrs emulation.

SHA2-512  - Instruction support for SHA512 Hash algorithm (e.g SHA512H,
	    SHA512H2, SHA512U0, SHA512SU1)
SHA3 	  - SHA3 crypto instructions (EOR3, RAX1, XAR, BCAX).
SM3	  - Instruction support for Chinese cryptography algorithm SM3
SM4 	  - Instruction support for Chinese cryptography algorithm SM4
DP	  - Dot Product instructions (UDOT, SDOT).

Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Dave Martin &lt;dave.martin@arm.com&gt;
Cc: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f5e035f8694c3bdddc66ea46ecda965ee6853718 ]

ARMv8-A adds a few optional features for ARMv8.2 and ARMv8.3.
Expose them to the userspace via HWCAPs and mrs emulation.

SHA2-512  - Instruction support for SHA512 Hash algorithm (e.g SHA512H,
	    SHA512H2, SHA512U0, SHA512SU1)
SHA3 	  - SHA3 crypto instructions (EOR3, RAX1, XAR, BCAX).
SM3	  - Instruction support for Chinese cryptography algorithm SM3
SM4 	  - Instruction support for Chinese cryptography algorithm SM4
DP	  - Dot Product instructions (UDOT, SDOT).

Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Dave Martin &lt;dave.martin@arm.com&gt;
Cc: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: rio500: Remove Rio 500 kernel driver</title>
<updated>2019-10-17T20:43:20+00:00</updated>
<author>
<name>Bastien Nocera</name>
<email>hadess@hadess.net</email>
</author>
<published>2019-09-23T16:18:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63469e0ab70251f247e58761f046fe5de5e2156d'/>
<id>63469e0ab70251f247e58761f046fe5de5e2156d</id>
<content type='text'>
commit 015664d15270a112c2371d812f03f7c579b35a73 upstream.

The Rio500 kernel driver has not been used by Rio500 owners since 2001
not long after the rio500 project added support for a user-space USB stack
through the very first versions of usbdevfs and then libusb.

Support for the kernel driver was removed from the upstream utilities
in 2008:
https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db

Cc: Cesar Miquel &lt;miquel@df.uba.ar&gt;
Signed-off-by: Bastien Nocera &lt;hadess@hadess.net&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 015664d15270a112c2371d812f03f7c579b35a73 upstream.

The Rio500 kernel driver has not been used by Rio500 owners since 2001
not long after the rio500 project added support for a user-space USB stack
through the very first versions of usbdevfs and then libusb.

Support for the kernel driver was removed from the upstream utilities
in 2008:
https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db

Cc: Cesar Miquel &lt;miquel@df.uba.ar&gt;
Signed-off-by: Bastien Nocera &lt;hadess@hadess.net&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h</title>
<updated>2019-08-29T06:26:43+00:00</updated>
<author>
<name>Tom Lendacky</name>
<email>thomas.lendacky@amd.com</email>
</author>
<published>2019-08-19T15:52:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0bfaf1c88b589d51d9cbf0758e5fd987004ce789'/>
<id>0bfaf1c88b589d51d9cbf0758e5fd987004ce789</id>
<content type='text'>
commit c49a0a80137c7ca7d6ced4c812c9e07a949f6f24 upstream.

There have been reports of RDRAND issues after resuming from suspend on
some AMD family 15h and family 16h systems. This issue stems from a BIOS
not performing the proper steps during resume to ensure RDRAND continues
to function properly.

RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be
reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND
support using CPUID, including the kernel, will believe that RDRAND is
not supported.

Update the CPU initialization to clear the RDRAND CPUID bit for any family
15h and 16h processor that supports RDRAND. If it is known that the family
15h or family 16h system does not have an RDRAND resume issue or that the
system will not be placed in suspend, the "rdrand=force" kernel parameter
can be used to stop the clearing of the RDRAND CPUID bit.

Additionally, update the suspend and resume path to save and restore the
MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in
place after resuming from suspend.

Note, that clearing the RDRAND CPUID bit does not prevent a processor
that normally supports the RDRAND instruction from executing it. So any
code that determined the support based on family and model won't #UD.

Signed-off-by: Tom Lendacky &lt;thomas.lendacky@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Chen Yu &lt;yu.c.chen@intel.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: "linux-doc@vger.kernel.org" &lt;linux-doc@vger.kernel.org&gt;
Cc: "linux-pm@vger.kernel.org" &lt;linux-pm@vger.kernel.org&gt;
Cc: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Pavel Machek &lt;pavel@ucw.cz&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: "x86@kernel.org" &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c49a0a80137c7ca7d6ced4c812c9e07a949f6f24 upstream.

There have been reports of RDRAND issues after resuming from suspend on
some AMD family 15h and family 16h systems. This issue stems from a BIOS
not performing the proper steps during resume to ensure RDRAND continues
to function properly.

RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be
reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND
support using CPUID, including the kernel, will believe that RDRAND is
not supported.

Update the CPU initialization to clear the RDRAND CPUID bit for any family
15h and 16h processor that supports RDRAND. If it is known that the family
15h or family 16h system does not have an RDRAND resume issue or that the
system will not be placed in suspend, the "rdrand=force" kernel parameter
can be used to stop the clearing of the RDRAND CPUID bit.

Additionally, update the suspend and resume path to save and restore the
MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in
place after resuming from suspend.

Note, that clearing the RDRAND CPUID bit does not prevent a processor
that normally supports the RDRAND instruction from executing it. So any
code that determined the support based on family and model won't #UD.

Signed-off-by: Tom Lendacky &lt;thomas.lendacky@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Chen Yu &lt;yu.c.chen@intel.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: "linux-doc@vger.kernel.org" &lt;linux-doc@vger.kernel.org&gt;
Cc: "linux-pm@vger.kernel.org" &lt;linux-pm@vger.kernel.org&gt;
Cc: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Pavel Machek &lt;pavel@ucw.cz&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: "x86@kernel.org" &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: add bpf_jit_limit knob to restrict unpriv allocations</title>
<updated>2019-08-25T08:50:03+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2019-08-16T22:05:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a1fe647042affe713a17243cd10e9b25f3d83948'/>
<id>a1fe647042affe713a17243cd10e9b25f3d83948</id>
<content type='text'>
commit ede95a63b5e84ddeea6b0c473b36ab8bfd8c6ce3 upstream.

Rick reported that the BPF JIT could potentially fill the entire module
space with BPF programs from unprivileged users which would prevent later
attempts to load normal kernel modules or privileged BPF programs, for
example. If JIT was enabled but unsuccessful to generate the image, then
before commit 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
we would always fall back to the BPF interpreter. Nowadays in the case
where the CONFIG_BPF_JIT_ALWAYS_ON could be set, then the load will abort
with a failure since the BPF interpreter was compiled out.

Add a global limit and enforce it for unprivileged users such that in case
of BPF interpreter compiled out we fail once the limit has been reached
or we fall back to BPF interpreter earlier w/o using module mem if latter
was compiled in. In a next step, fair share among unprivileged users can
be resolved in particular for the case where we would fail hard once limit
is reached.

Fixes: 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
Fixes: 0a14842f5a3c ("net: filter: Just In Time compiler for x86-64")
Co-Developed-by: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: LKML &lt;linux-kernel@vger.kernel.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Ben Hutchings &lt;ben.hutchings@codethink.co.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ede95a63b5e84ddeea6b0c473b36ab8bfd8c6ce3 upstream.

Rick reported that the BPF JIT could potentially fill the entire module
space with BPF programs from unprivileged users which would prevent later
attempts to load normal kernel modules or privileged BPF programs, for
example. If JIT was enabled but unsuccessful to generate the image, then
before commit 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
we would always fall back to the BPF interpreter. Nowadays in the case
where the CONFIG_BPF_JIT_ALWAYS_ON could be set, then the load will abort
with a failure since the BPF interpreter was compiled out.

Add a global limit and enforce it for unprivileged users such that in case
of BPF interpreter compiled out we fail once the limit has been reached
or we fall back to BPF interpreter earlier w/o using module mem if latter
was compiled in. In a next step, fair share among unprivileged users can
be resolved in particular for the case where we would fail hard once limit
is reached.

Fixes: 290af86629b2 ("bpf: introduce BPF_JIT_ALWAYS_ON config")
Fixes: 0a14842f5a3c ("net: filter: Just In Time compiler for x86-64")
Co-Developed-by: Rick Edgecombe &lt;rick.p.edgecombe@intel.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: LKML &lt;linux-kernel@vger.kernel.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Ben Hutchings &lt;ben.hutchings@codethink.co.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Documentation: Add swapgs description to the Spectre v1 documentation</title>
<updated>2019-08-06T17:05:30+00:00</updated>
<author>
<name>Josh Poimboeuf</name>
<email>jpoimboe@redhat.com</email>
</author>
<published>2019-08-03T19:21:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d4187064959c0df9f3e610de02cb3b822c64b88d'/>
<id>d4187064959c0df9f3e610de02cb3b822c64b88d</id>
<content type='text'>
commit 4c92057661a3412f547ede95715641d7ee16ddac upstream

Add documentation to the Spectre document about the new swapgs variant of
Spectre v1.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4c92057661a3412f547ede95715641d7ee16ddac upstream

Add documentation to the Spectre document about the new swapgs variant of
Spectre v1.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
