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<title>user/sven/linux.git/arch, branch v6.4.3</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2023-07-05T17:30:30Z</updated>
<entry>
<title>arch/arm64/mm/fault: Fix undeclared variable error in do_page_fault()</title>
<updated>2023-07-05T17:30:30Z</updated>
<author>
<name>SeongJae Park</name>
<email>sj@kernel.org</email>
</author>
<published>2023-07-04T01:00:03Z</published>
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<id>urn:sha1:ba0f198721f4efeaf34c2c71a7c7512349d9ffbe</id>
<content type='text'>
commit 24be4d0b46bb0c3c1dc7bacd30957d6144a70dfc upstream.

Commit ae870a68b5d1 ("arm64/mm: Convert to using
lock_mm_and_find_vma()") made do_page_fault() to use 'vma' even if
CONFIG_PER_VMA_LOCK is not defined, but the declaration is still in the
ifdef.

As a result, building kernel without the config fails with undeclared
variable error as below:

    arch/arm64/mm/fault.c: In function 'do_page_fault':
    arch/arm64/mm/fault.c:624:2: error: 'vma' undeclared (first use in this function); did you mean 'vmap'?
      624 |  vma = lock_mm_and_find_vma(mm, addr, regs);
          |  ^~~
          |  vmap

Fix it by moving the declaration out of the ifdef.

Fixes: ae870a68b5d1 ("arm64/mm: Convert to using lock_mm_and_find_vma()")
Signed-off-by: SeongJae Park &lt;sj@kernel.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>
</entry>
<entry>
<title>csky: fix up lock_mm_and_find_vma() conversion</title>
<updated>2023-07-01T11:12:41Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-30T06:34:29Z</published>
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<id>urn:sha1:87d780e048bda5cda800f8ffc5199ecdd53b1412</id>
<content type='text'>
commit e55e5df193d247a38a5e1ac65a5316a0adcc22fa upstream.

As already mentioned in my merge message for the 'expand-stack' branch,
we have something like 24 different versions of the page fault path for
all our different architectures, all just _slightly_ different due to
various historical reasons (usually related to exactly when they
branched off the original i386 version, and the details of the other
architectures they had in their history).

And a few of them had some silly mistake in the conversion.

Most of the architectures call the faulting address 'address' in the
fault path.  But not all.  Some just call it 'addr'.  And if you end up
doing a bit too much copy-and-paste, you end up with the wrong version
in the places that do it differently.

In this case it was csky.

Fixes: a050ba1e7422 ("mm/fault: convert remaining simple cases to lock_mm_and_find_vma()")
Reported-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>parisc: fix expand_stack() conversion</title>
<updated>2023-07-01T11:12:41Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-30T06:04:57Z</published>
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<id>urn:sha1:0d98e5325f1f423be19c6124905133951cc17198</id>
<content type='text'>
commit ea3f8272876f2958463992f6736ab690fde7fa9c upstream.

In commit 8d7071af8907 ("mm: always expand the stack with the mmap write
lock held") I tried to deal with the remaining odd page fault handling
cases.  The oddest one is ia64, which has stacks that grow both up and
down.  And because ia64 was _so_ odd, I asked people to verify the end
result.

But a close second oddity is parisc, which is the only one that has a
main stack growing up (our "CONFIG_STACK_GROWSUP" config option).  But
it looked obvious enough that I didn't worry about it.

I should have worried a bit more.  Not because it was particularly
complex, but because I just used the wrong variable name.

The previous vma isn't called "prev", it's called "prev_vma".  Blush.

Fixes: 8d7071af8907 ("mm: always expand the stack with the mmap write lock held")
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>sparc32: fix lock_mm_and_find_vma() conversion</title>
<updated>2023-07-01T11:12:41Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-30T03:41:24Z</published>
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<id>urn:sha1:23d1e960cd12b38000908839c6b2ff494223149e</id>
<content type='text'>
commit 0b26eadbf200abf6c97c6d870286c73219cdac65 upstream.

The sparc32 conversion to lock_mm_and_find_vma() in commit a050ba1e7422
("mm/fault: convert remaining simple cases to lock_mm_and_find_vma()")
missed the fact that we didn't actually have a 'regs' pointer available
in the 'force_user_fault()' case.

It's there in the regular page fault path ("do_sparc_fault()"), but not
the window underflow/overflow paths.

Which is all fine - we can just pass in a NULL pointer.  The register
state is only used to avoid deadlock with kernel faults, which is not
the case for any of these register window faults.

Reported-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Fixes: a050ba1e7422 ("mm/fault: convert remaining simple cases to lock_mm_and_find_vma()")
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Naresh Kamboju &lt;naresh.kamboju@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm: always expand the stack with the mmap write lock held</title>
<updated>2023-07-01T11:12:40Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-24T20:45:51Z</published>
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<id>urn:sha1:fb32951c89030c5f9944ca8aa10301d7eb733b49</id>
<content type='text'>
commit 8d7071af890768438c14db6172cc8f9f4d04e184 upstream.

This finishes the job of always holding the mmap write lock when
extending the user stack vma, and removes the 'write_locked' argument
from the vm helper functions again.

For some cases, we just avoid expanding the stack at all: drivers and
page pinning really shouldn't be extending any stacks.  Let's see if any
strange users really wanted that.

It's worth noting that architectures that weren't converted to the new
lock_mm_and_find_vma() helper function are left using the legacy
"expand_stack()" function, but it has been changed to drop the mmap_lock
and take it for writing while expanding the vma.  This makes it fairly
straightforward to convert the remaining architectures.

As a result of dropping and re-taking the lock, the calling conventions
for this function have also changed, since the old vma may no longer be
valid.  So it will now return the new vma if successful, and NULL - and
the lock dropped - if the area could not be extended.

Tested-by: Vegard Nossum &lt;vegard.nossum@oracle.com&gt;
Tested-by: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt; # ia64
Tested-by: Frank Scheiner &lt;frank.scheiner@web.de&gt; # ia64
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>powerpc/mm: convert coprocessor fault to lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:12:39Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-24T18:17:05Z</published>
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<id>urn:sha1:accf6d0c5832e3a880e6798fc4cc76d49573e7f4</id>
<content type='text'>
commit 2cd76c50d0b41cec5c87abfcdf25b236a2793fb6 upstream.

This is one of the simple cases, except there's no pt_regs pointer.
Which is fine, as lock_mm_and_find_vma() is set up to work fine with a
NULL pt_regs.

Powerpc already enabled LOCK_MM_AND_FIND_VMA for the main CPU faulting,
so we can just use the helper without any extra work.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm/fault: convert remaining simple cases to lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:12:39Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-06-24T17:55:38Z</published>
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<id>urn:sha1:203cfe05efc84b6d888fdc37862c53c6ee64a006</id>
<content type='text'>
commit a050ba1e7422f2cc60ff8bfde3f96d34d00cb585 upstream.

This does the simple pattern conversion of alpha, arc, csky, hexagon,
loongarch, nios2, sh, sparc32, and xtensa to the lock_mm_and_find_vma()
helper.  They all have the regular fault handling pattern without odd
special cases.

The remaining architectures all have something that keeps us from a
straightforward conversion: ia64 and parisc have stacks that can grow
both up as well as down (and ia64 has special address region checks).

And m68k, microblaze, openrisc, sparc64, and um end up having extra
rules about only expanding the stack down a limited amount below the
user space stack pointer.  That is something that x86 used to do too
(long long ago), and it probably could just be skipped, but it still
makes the conversion less than trivial.

Note that this conversion was done manually and with the exception of
alpha without any build testing, because I have a fairly limited cross-
building environment.  The cases are all simple, and I went through the
changes several times, but...

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>arm/mm: Convert to using lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:12:39Z</updated>
<author>
<name>Ben Hutchings</name>
<email>ben@decadent.org.uk</email>
</author>
<published>2023-06-22T19:24:30Z</published>
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<id>urn:sha1:4e3fb74f605054555693031083248903dc2796d6</id>
<content type='text'>
commit 8b35ca3e45e35a26a21427f35d4093606e93ad0a upstream.

arm has an additional check for address &lt; FIRST_USER_ADDRESS before
expanding the stack.  Since FIRST_USER_ADDRESS is defined everywhere
(generally as 0), move that check to the generic expand_downwards().

Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>riscv/mm: Convert to using lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:12:39Z</updated>
<author>
<name>Ben Hutchings</name>
<email>ben@decadent.org.uk</email>
</author>
<published>2023-06-22T18:18:18Z</published>
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<id>urn:sha1:7e99b9821acc954f407da09b31a4a95d35dd147d</id>
<content type='text'>
commit 7267ef7b0b77f4ed23b7b3c87d8eca7bd9c2d007 upstream.

Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mips/mm: Convert to using lock_mm_and_find_vma()</title>
<updated>2023-07-01T11:12:39Z</updated>
<author>
<name>Ben Hutchings</name>
<email>ben@decadent.org.uk</email>
</author>
<published>2023-06-22T16:47:40Z</published>
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<id>urn:sha1:929eb6b2a6901d5c7ef13a6aab0a07c31a603a05</id>
<content type='text'>
commit 4bce37a68ff884e821a02a731897a8119e0c37b7 upstream.

Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
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