<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/Kconfig, branch linux-5.4.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>init: Provide arch_cpu_finalize_init()</title>
<updated>2023-08-08T17:56:33+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2023-06-13T23:39:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=afe787cf253b4e0d179ee5c01593650a839cf2b4'/>
<id>afe787cf253b4e0d179ee5c01593650a839cf2b4</id>
<content type='text'>
commit 7725acaa4f0c04fbefb0e0d342635b967bb7d414 upstream

check_bugs() has become a dumping ground for all sorts of activities to
finalize the CPU initialization before running the rest of the init code.

Most are empty, a few do actual bug checks, some do alternative patching
and some cobble a CPU advertisement string together....

Aside of that the current implementation requires duplicated function
declaration and mostly empty header files for them.

Provide a new function arch_cpu_finalize_init(). Provide a generic
declaration if CONFIG_ARCH_HAS_CPU_FINALIZE_INIT is selected and a stub
inline otherwise.

This requires a temporary #ifdef in start_kernel() which will be removed
along with check_bugs() once the architectures are converted over.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/r/20230613224544.957805717@linutronix.de
Signed-off-by: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&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 7725acaa4f0c04fbefb0e0d342635b967bb7d414 upstream

check_bugs() has become a dumping ground for all sorts of activities to
finalize the CPU initialization before running the rest of the init code.

Most are empty, a few do actual bug checks, some do alternative patching
and some cobble a CPU advertisement string together....

Aside of that the current implementation requires duplicated function
declaration and mostly empty header files for them.

Provide a new function arch_cpu_finalize_init(). Provide a generic
declaration if CONFIG_ARCH_HAS_CPU_FINALIZE_INIT is selected and a stub
inline otherwise.

This requires a temporary #ifdef in start_kernel() which will be removed
along with check_bugs() once the architectures are converted over.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/r/20230613224544.957805717@linutronix.de
Signed-off-by: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>locking/refcount: Consolidate implementations of refcount_t</title>
<updated>2022-07-29T15:14:17+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will@kernel.org</email>
</author>
<published>2019-11-21T11:59:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d0d583484d2ed9f5903edbbfa7e2a68f78b950b0'/>
<id>d0d583484d2ed9f5903edbbfa7e2a68f78b950b0</id>
<content type='text'>
[ Upstream commit fb041bb7c0a918b95c6889fc965cdc4a75b4c0ca ]

The generic implementation of refcount_t should be good enough for
everybody, so remove ARCH_HAS_REFCOUNT and REFCOUNT_FULL entirely,
leaving the generic implementation enabled unconditionally.

Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Reviewed-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Tested-by: Hanjun Guo &lt;guohanjun@huawei.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Elena Reshetova &lt;elena.reshetova@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lkml.kernel.org/r/20191121115902.2551-9-will@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fb041bb7c0a918b95c6889fc965cdc4a75b4c0ca ]

The generic implementation of refcount_t should be good enough for
everybody, so remove ARCH_HAS_REFCOUNT and REFCOUNT_FULL entirely,
leaving the generic implementation enabled unconditionally.

Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Reviewed-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Tested-by: Hanjun Guo &lt;guohanjun@huawei.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Elena Reshetova &lt;elena.reshetova@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lkml.kernel.org/r/20191121115902.2551-9-will@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert: "ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS"</title>
<updated>2020-12-30T10:51:47+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2020-12-14T17:33:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6001db0272dad842c151151f5a9b89a53a7f7520'/>
<id>6001db0272dad842c151151f5a9b89a53a7f7520</id>
<content type='text'>
commit adab66b71abfe206a020f11e561f4df41f0b2aba upstream.

It was believed that metag was the only architecture that required the ring
buffer to keep 8 byte words aligned on 8 byte architectures, and with its
removal, it was assumed that the ring buffer code did not need to handle
this case. It appears that sparc64 also requires this.

The following was reported on a sparc64 boot up:

   kernel: futex hash table entries: 65536 (order: 9, 4194304 bytes, linear)
   kernel: Running postponed tracer tests:
   kernel: Testing tracer function:
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: Kernel unaligned access at TPC[552a24] trace_function+0x44/0x140
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: Kernel unaligned access at TPC[552a24] trace_function+0x44/0x140
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: PASSED

Need to put back the 64BIT aligned code for the ring buffer.

Link: https://lore.kernel.org/r/CADxRZqzXQRYgKc=y-KV=S_yHL+Y8Ay2mh5ezeZUnpRvg+syWKw@mail.gmail.com

Cc: stable@vger.kernel.org
Fixes: 86b3de60a0b6 ("ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS")
Reported-by: Anatoly Pugachev &lt;matorola@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.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>
commit adab66b71abfe206a020f11e561f4df41f0b2aba upstream.

It was believed that metag was the only architecture that required the ring
buffer to keep 8 byte words aligned on 8 byte architectures, and with its
removal, it was assumed that the ring buffer code did not need to handle
this case. It appears that sparc64 also requires this.

The following was reported on a sparc64 boot up:

   kernel: futex hash table entries: 65536 (order: 9, 4194304 bytes, linear)
   kernel: Running postponed tracer tests:
   kernel: Testing tracer function:
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: Kernel unaligned access at TPC[552a24] trace_function+0x44/0x140
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: Kernel unaligned access at TPC[552a24] trace_function+0x44/0x140
   kernel: Kernel unaligned access at TPC[552a20] trace_function+0x40/0x140
   kernel: PASSED

Need to put back the 64BIT aligned code for the ring buffer.

Link: https://lore.kernel.org/r/CADxRZqzXQRYgKc=y-KV=S_yHL+Y8Ay2mh5ezeZUnpRvg+syWKw@mail.gmail.com

Cc: stable@vger.kernel.org
Fixes: 86b3de60a0b6 ("ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS")
Reported-by: Anatoly Pugachev &lt;matorola@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race</title>
<updated>2020-11-05T10:43:13+00:00</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2020-09-14T04:52:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=82e93f94ac653d57373f1368a4dcb066d24af490'/>
<id>82e93f94ac653d57373f1368a4dcb066d24af490</id>
<content type='text'>
[ Upstream commit d53c3dfb23c45f7d4f910c3a3ca84bf0a99c6143 ]

Reading and modifying current-&gt;mm and current-&gt;active_mm and switching
mm should be done with irqs off, to prevent races seeing an intermediate
state.

This is similar to commit 38cf307c1f20 ("mm: fix kthread_use_mm() vs TLB
invalidate"). At exec-time when the new mm is activated, the old one
should usually be single-threaded and no longer used, unless something
else is holding an mm_users reference (which may be possible).

Absent other mm_users, there is also a race with preemption and lazy tlb
switching. Consider the kernel_execve case where the current thread is
using a lazy tlb active mm:

  call_usermodehelper()
    kernel_execve()
      old_mm = current-&gt;mm;
      active_mm = current-&gt;active_mm;
      *** preempt *** --------------------&gt;  schedule()
                                               prev-&gt;active_mm = NULL;
                                               mmdrop(prev active_mm);
                                             ...
                      &lt;--------------------  schedule()
      current-&gt;mm = mm;
      current-&gt;active_mm = mm;
      if (!old_mm)
          mmdrop(active_mm);

If we switch back to the kernel thread from a different mm, there is a
double free of the old active_mm, and a missing free of the new one.

Closing this race only requires interrupts to be disabled while -&gt;mm
and -&gt;active_mm are being switched, but the TLB problem requires also
holding interrupts off over activate_mm. Unfortunately not all archs
can do that yet, e.g., arm defers the switch if irqs are disabled and
expects finish_arch_post_lock_switch() to be called to complete the
flush; um takes a blocking lock in activate_mm().

So as a first step, disable interrupts across the mm/active_mm updates
to close the lazy tlb preempt race, and provide an arch option to
extend that to activate_mm which allows architectures doing IPI based
TLB shootdowns to close the second race.

This is a bit ugly, but in the interest of fixing the bug and backporting
before all architectures are converted this is a compromise.

Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20200914045219.3736466-2-npiggin@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d53c3dfb23c45f7d4f910c3a3ca84bf0a99c6143 ]

Reading and modifying current-&gt;mm and current-&gt;active_mm and switching
mm should be done with irqs off, to prevent races seeing an intermediate
state.

This is similar to commit 38cf307c1f20 ("mm: fix kthread_use_mm() vs TLB
invalidate"). At exec-time when the new mm is activated, the old one
should usually be single-threaded and no longer used, unless something
else is holding an mm_users reference (which may be possible).

Absent other mm_users, there is also a race with preemption and lazy tlb
switching. Consider the kernel_execve case where the current thread is
using a lazy tlb active mm:

  call_usermodehelper()
    kernel_execve()
      old_mm = current-&gt;mm;
      active_mm = current-&gt;active_mm;
      *** preempt *** --------------------&gt;  schedule()
                                               prev-&gt;active_mm = NULL;
                                               mmdrop(prev active_mm);
                                             ...
                      &lt;--------------------  schedule()
      current-&gt;mm = mm;
      current-&gt;active_mm = mm;
      if (!old_mm)
          mmdrop(active_mm);

If we switch back to the kernel thread from a different mm, there is a
double free of the old active_mm, and a missing free of the new one.

Closing this race only requires interrupts to be disabled while -&gt;mm
and -&gt;active_mm are being switched, but the TLB problem requires also
holding interrupts off over activate_mm. Unfortunately not all archs
can do that yet, e.g., arm defers the switch if irqs are disabled and
expects finish_arch_post_lock_switch() to be called to complete the
flush; um takes a blocking lock in activate_mm().

So as a first step, disable interrupts across the mm/active_mm updates
to close the lazy tlb preempt race, and provide an arch option to
extend that to activate_mm which allows architectures doing IPI based
TLB shootdowns to close the second race.

This is a bit ugly, but in the interest of fixing the bug and backporting
before all architectures are converted this is a compromise.

Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20200914045219.3736466-2-npiggin@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>asm-generic/tlb: add missing CONFIG symbol</title>
<updated>2020-02-24T07:37:02+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-02-04T01:36:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7ceb32672b1e1dbdef75f3e175517fa20460f0c9'/>
<id>7ceb32672b1e1dbdef75f3e175517fa20460f0c9</id>
<content type='text'>
[ Upstream commit 27796d03c9c4b2b937ed4cc2b10f21559ad5a8c9 ]

Without this the symbol will not actually end up in .config files.

Link: http://lkml.kernel.org/r/20200116064531.483522-6-aneesh.kumar@linux.ibm.com
Fixes: a30e32bd79e9 ("asm-generic/tlb: Provide generic tlb_flush() based on flush_tlb_mm()")
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 27796d03c9c4b2b937ed4cc2b10f21559ad5a8c9 ]

Without this the symbol will not actually end up in .config files.

Link: http://lkml.kernel.org/r/20200116064531.483522-6-aneesh.kumar@linux.ibm.com
Fixes: a30e32bd79e9 ("asm-generic/tlb: Provide generic tlb_flush() based on flush_tlb_mm()")
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush</title>
<updated>2020-02-11T12:35:42+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-02-04T01:36:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=806cabd3117f46b505d7a7fdb33d3ce1db99e77a'/>
<id>806cabd3117f46b505d7a7fdb33d3ce1db99e77a</id>
<content type='text'>
commit 0ed1325967ab5f7a4549a2641c6ebe115f76e228 upstream.

Architectures for which we have hardware walkers of Linux page table
should flush TLB on mmu gather batch allocation failures and batch flush.
Some architectures like POWER supports multiple translation modes (hash
and radix) and in the case of POWER only radix translation mode needs the
above TLBI.  This is because for hash translation mode kernel wants to
avoid this extra flush since there are no hardware walkers of linux page
table.  With radix translation, the hardware also walks linux page table
and with that, kernel needs to make sure to TLB invalidate page walk cache
before page table pages are freed.

More details in commit d86564a2f085 ("mm/tlb, x86/mm: Support invalidating
TLB caches for RCU_TABLE_FREE")

The changes to sparc are to make sure we keep the old behavior since we
are now removing HAVE_RCU_TABLE_NO_INVALIDATE.  The default value for
tlb_needs_table_invalidate is to always force an invalidate and sparc can
avoid the table invalidate.  Hence we define tlb_needs_table_invalidate to
false for sparc architecture.

Link: http://lkml.kernel.org/r/20200116064531.483522-3-aneesh.kumar@linux.ibm.com
Fixes: a46cc7a90fd8 ("powerpc/mm/radix: Improve TLB/PWC flushes")
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;	[powerpc]
Cc: &lt;stable@vger.kernel.org&gt;	[4.14+]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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>
commit 0ed1325967ab5f7a4549a2641c6ebe115f76e228 upstream.

Architectures for which we have hardware walkers of Linux page table
should flush TLB on mmu gather batch allocation failures and batch flush.
Some architectures like POWER supports multiple translation modes (hash
and radix) and in the case of POWER only radix translation mode needs the
above TLBI.  This is because for hash translation mode kernel wants to
avoid this extra flush since there are no hardware walkers of linux page
table.  With radix translation, the hardware also walks linux page table
and with that, kernel needs to make sure to TLB invalidate page walk cache
before page table pages are freed.

More details in commit d86564a2f085 ("mm/tlb, x86/mm: Support invalidating
TLB caches for RCU_TABLE_FREE")

The changes to sparc are to make sure we keep the old behavior since we
are now removing HAVE_RCU_TABLE_NO_INVALIDATE.  The default value for
tlb_needs_table_invalidate is to always force an invalidate and sparc can
avoid the table invalidate.  Hence we define tlb_needs_table_invalidate to
false for sparc architecture.

Link: http://lkml.kernel.org/r/20200116064531.483522-3-aneesh.kumar@linux.ibm.com
Fixes: a46cc7a90fd8 ("powerpc/mm/radix: Improve TLB/PWC flushes")
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;	[powerpc]
Cc: &lt;stable@vger.kernel.org&gt;	[4.14+]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64, mm: make randomization selected by generic topdown mmap layout</title>
<updated>2019-09-24T22:54:11+00:00</updated>
<author>
<name>Alexandre Ghiti</name>
<email>alex@ghiti.fr</email>
</author>
<published>2019-09-23T22:38:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e7142bf5d231f3ccdf6ea6764d5080999b8e299d'/>
<id>e7142bf5d231f3ccdf6ea6764d5080999b8e299d</id>
<content type='text'>
This commits selects ARCH_HAS_ELF_RANDOMIZE when an arch uses the generic
topdown mmap layout functions so that this security feature is on by
default.

Note that this commit also removes the possibility for arm64 to have elf
randomization and no MMU: without MMU, the security added by randomization
is worth nothing.

Link: http://lkml.kernel.org/r/20190730055113.23635-6-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This commits selects ARCH_HAS_ELF_RANDOMIZE when an arch uses the generic
topdown mmap layout functions so that this security feature is on by
default.

Note that this commit also removes the possibility for arm64 to have elf
randomization and no MMU: without MMU, the security added by randomization
is worth nothing.

Link: http://lkml.kernel.org/r/20190730055113.23635-6-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64, mm: move generic mmap layout functions to mm</title>
<updated>2019-09-24T22:54:11+00:00</updated>
<author>
<name>Alexandre Ghiti</name>
<email>alex@ghiti.fr</email>
</author>
<published>2019-09-23T22:38:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=67f3977f805b34cf0e41090679800d2091d41d49'/>
<id>67f3977f805b34cf0e41090679800d2091d41d49</id>
<content type='text'>
arm64 handles top-down mmap layout in a way that can be easily reused by
other architectures, so make it available in mm.  It then introduces a new
config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other
architectures to benefit from those functions.  Note that this new config
depends on MMU being enabled, if selected without MMU support, a warning
will be thrown.

Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
arm64 handles top-down mmap layout in a way that can be easily reused by
other architectures, so make it available in mm.  It then introduces a new
config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other
architectures to benefit from those functions.  Note that this new config
depends on MMU being enabled, if selected without MMU support, a warning
will be thrown.

Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: James Hogan &lt;jhogan@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@sifive.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2019-09-20T18:48:06+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-20T18:48:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=45824fc0da6e46cc5d563105e1eaaf3098a686f9'/>
<id>45824fc0da6e46cc5d563105e1eaaf3098a686f9</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:
 "This is a bit late, partly due to me travelling, and partly due to a
  power outage knocking out some of my test systems *while* I was
  travelling.

   - Initial support for running on a system with an Ultravisor, which
     is software that runs below the hypervisor and protects guests
     against some attacks by the hypervisor.

   - Support for building the kernel to run as a "Secure Virtual
     Machine", ie. as a guest capable of running on a system with an
     Ultravisor.

   - Some changes to our DMA code on bare metal, to allow devices with
     medium sized DMA masks (&gt; 32 &amp;&amp; &lt; 59 bits) to use more than 2GB of
     DMA space.

   - Support for firmware assisted crash dumps on bare metal (powernv).

   - Two series fixing bugs in and refactoring our PCI EEH code.

   - A large series refactoring our exception entry code to use gas
     macros, both to make it more readable and also enable some future
     optimisations.

  As well as many cleanups and other minor features &amp; fixups.

  Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
  Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
  JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
  Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
  Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
  Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
  Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
  Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
  Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
  Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
  Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
  Lendacky, Vasant Hegde"

* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
  powerpc/mm/mce: Keep irqs disabled during lockless page table walk
  powerpc: Use ftrace_graph_ret_addr() when unwinding
  powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
  ftrace: Look up the address of return_to_handler() using helpers
  powerpc: dump kernel log before carrying out fadump or kdump
  docs: powerpc: Add missing documentation reference
  powerpc/xmon: Fix output of XIVE IPI
  powerpc/xmon: Improve output of XIVE interrupts
  powerpc/mm/radix: remove useless kernel messages
  powerpc/fadump: support holes in kernel boot memory area
  powerpc/fadump: remove RMA_START and RMA_END macros
  powerpc/fadump: update documentation about option to release opalcore
  powerpc/fadump: consider f/w load area
  powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
  powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
  powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
  powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
  powerpc/fadump: improve how crashed kernel's memory is reserved
  powerpc/fadump: consider reserved ranges while releasing memory
  powerpc/fadump: make crash memory ranges array allocation generic
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:
 "This is a bit late, partly due to me travelling, and partly due to a
  power outage knocking out some of my test systems *while* I was
  travelling.

   - Initial support for running on a system with an Ultravisor, which
     is software that runs below the hypervisor and protects guests
     against some attacks by the hypervisor.

   - Support for building the kernel to run as a "Secure Virtual
     Machine", ie. as a guest capable of running on a system with an
     Ultravisor.

   - Some changes to our DMA code on bare metal, to allow devices with
     medium sized DMA masks (&gt; 32 &amp;&amp; &lt; 59 bits) to use more than 2GB of
     DMA space.

   - Support for firmware assisted crash dumps on bare metal (powernv).

   - Two series fixing bugs in and refactoring our PCI EEH code.

   - A large series refactoring our exception entry code to use gas
     macros, both to make it more readable and also enable some future
     optimisations.

  As well as many cleanups and other minor features &amp; fixups.

  Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
  Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
  JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
  Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
  Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
  Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
  Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
  Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
  Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
  Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
  Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
  Lendacky, Vasant Hegde"

* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
  powerpc/mm/mce: Keep irqs disabled during lockless page table walk
  powerpc: Use ftrace_graph_ret_addr() when unwinding
  powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
  ftrace: Look up the address of return_to_handler() using helpers
  powerpc: dump kernel log before carrying out fadump or kdump
  docs: powerpc: Add missing documentation reference
  powerpc/xmon: Fix output of XIVE IPI
  powerpc/xmon: Improve output of XIVE interrupts
  powerpc/mm/radix: remove useless kernel messages
  powerpc/fadump: support holes in kernel boot memory area
  powerpc/fadump: remove RMA_START and RMA_END macros
  powerpc/fadump: update documentation about option to release opalcore
  powerpc/fadump: consider f/w load area
  powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
  powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
  powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
  powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
  powerpc/fadump: improve how crashed kernel's memory is reserved
  powerpc/fadump: consider reserved ranges while releasing memory
  powerpc/fadump: make crash memory ranges array allocation generic
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2019-09-20T15:36:47+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-20T15:36:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d7b0827f28ab3a4fd65864451ffefa695e3255fd'/>
<id>d7b0827f28ab3a4fd65864451ffefa695e3255fd</id>
<content type='text'>
Pull Kbuild updates from Masahiro Yamada:

 - add modpost warn exported symbols marked as 'static' because 'static'
   and EXPORT_SYMBOL is an odd combination

 - break the build early if gold linker is used

 - optimize the Bison rule to produce .c and .h files by a single
   pattern rule

 - handle PREEMPT_RT in the module vermagic and UTS_VERSION

 - warn CONFIG options leaked to the user-space except existing ones

 - make single targets work properly

 - rebuild modules when module linker scripts are updated

 - split the module final link stage into scripts/Makefile.modfinal

 - fix the missed error code in merge_config.sh

 - improve the error message displayed on the attempt of the O= build in
   unclean source tree

 - remove 'clean-dirs' syntax

 - disable -Wimplicit-fallthrough warning for Clang

 - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC

 - remove ARCH_{CPP,A,C}FLAGS variables

 - add $(BASH) to run bash scripts

 - change *CFLAGS_&lt;basetarget&gt;.o to take the relative path to $(obj)
   instead of the basename

 - stop suppressing Clang's -Wunused-function warnings when W=1

 - fix linux/export.h to avoid genksyms calculating CRC of trimmed
   exported symbols

 - misc cleanups

* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
  genksyms: convert to SPDX License Identifier for lex.l and parse.y
  modpost: use __section in the output to *.mod.c
  modpost: use MODULE_INFO() for __module_depends
  export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
  export.h: remove defined(__KERNEL__), which is no longer needed
  kbuild: allow Clang to find unused static inline functions for W=1 build
  kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
  kbuild: refactor scripts/Makefile.extrawarn
  merge_config.sh: ignore unwanted grep errors
  kbuild: change *FLAGS_&lt;basetarget&gt;.o to take the path relative to $(obj)
  modpost: add NOFAIL to strndup
  modpost: add guid_t type definition
  kbuild: add $(BASH) to run scripts with bash-extension
  kbuild: remove ARCH_{CPP,A,C}FLAGS
  kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
  kbuild: Do not enable -Wimplicit-fallthrough for clang for now
  kbuild: clean up subdir-ymn calculation in Makefile.clean
  kbuild: remove unneeded '+' marker from cmd_clean
  kbuild: remove clean-dirs syntax
  kbuild: check clean srctree even earlier
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Kbuild updates from Masahiro Yamada:

 - add modpost warn exported symbols marked as 'static' because 'static'
   and EXPORT_SYMBOL is an odd combination

 - break the build early if gold linker is used

 - optimize the Bison rule to produce .c and .h files by a single
   pattern rule

 - handle PREEMPT_RT in the module vermagic and UTS_VERSION

 - warn CONFIG options leaked to the user-space except existing ones

 - make single targets work properly

 - rebuild modules when module linker scripts are updated

 - split the module final link stage into scripts/Makefile.modfinal

 - fix the missed error code in merge_config.sh

 - improve the error message displayed on the attempt of the O= build in
   unclean source tree

 - remove 'clean-dirs' syntax

 - disable -Wimplicit-fallthrough warning for Clang

 - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC

 - remove ARCH_{CPP,A,C}FLAGS variables

 - add $(BASH) to run bash scripts

 - change *CFLAGS_&lt;basetarget&gt;.o to take the relative path to $(obj)
   instead of the basename

 - stop suppressing Clang's -Wunused-function warnings when W=1

 - fix linux/export.h to avoid genksyms calculating CRC of trimmed
   exported symbols

 - misc cleanups

* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
  genksyms: convert to SPDX License Identifier for lex.l and parse.y
  modpost: use __section in the output to *.mod.c
  modpost: use MODULE_INFO() for __module_depends
  export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
  export.h: remove defined(__KERNEL__), which is no longer needed
  kbuild: allow Clang to find unused static inline functions for W=1 build
  kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
  kbuild: refactor scripts/Makefile.extrawarn
  merge_config.sh: ignore unwanted grep errors
  kbuild: change *FLAGS_&lt;basetarget&gt;.o to take the path relative to $(obj)
  modpost: add NOFAIL to strndup
  modpost: add guid_t type definition
  kbuild: add $(BASH) to run scripts with bash-extension
  kbuild: remove ARCH_{CPP,A,C}FLAGS
  kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
  kbuild: Do not enable -Wimplicit-fallthrough for clang for now
  kbuild: clean up subdir-ymn calculation in Makefile.clean
  kbuild: remove unneeded '+' marker from cmd_clean
  kbuild: remove clean-dirs syntax
  kbuild: check clean srctree even earlier
  ...
</pre>
</div>
</content>
</entry>
</feed>
