linux-stable.git/arch/arm/include, branch v3.12.41 Linux kernel stable tree ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE 2015-04-09T12:13:43+00:00 Steven Capper steve.capper@linaro.org 2014-07-18T15:16:15+00:00 f0cd84895484b4ab98701654bc02791c472c7465 commit ded9477984690d026e46dd75e8157392cea3f13f upstream. For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> [dump.c is not in 3.12] 
commit ded9477984690d026e46dd75e8157392cea3f13f upstream.

For LPAE, we have the following means for encoding writable or dirty
ptes:
                              L_PTE_DIRTY       L_PTE_RDONLY
    !pte_dirty && !pte_write        0               1
    !pte_dirty && pte_write         0               1
    pte_dirty && !pte_write         1               1
    pte_dirty && pte_write          1               0

So we can't distinguish between writeable clean ptes and read only
ptes. This can cause problems with ptes being incorrectly flagged as
read only when they are writeable but not dirty.

This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58,
and adds additional logic to set AP[2] whenever the pte is read only
or not dirty. That way we can distinguish between clean writeable ptes
and read only ptes.

HugeTLB pages will use this new logic automatically.

We need to add some logic to Transparent HugePages to ensure that they
correctly interpret the revised pgprot permissions (L_PTE_RDONLY has
moved and no longer matches PMD_SECT_AP2). In the process of revising
THP, the names of the PMD software bits have been prefixed with L_ to
make them easier to distinguish from their hardware bit counterparts.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz> [dump.c is not in 3.12]
ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear 2015-04-09T12:13:42+00:00 Steven Capper steve.capper@linaro.org 2014-07-18T15:15:27+00:00 aaca16dc9198d855b58bccd200918b9af138d6be commit f2950706871c4b6e8c0f0d7c3f62d35930b8de63 upstream. Long descriptors on ARM are 64 bits, and some pte functions such as pte_dirty return a bitwise-and of a flag with the pte value. If the flag to be tested resides in the upper 32 bits of the pte, then we run into the danger of the result being dropped if downcast. For example: gather_stats(page, md, pte_dirty(*pte), 1); where pte_dirty(*pte) is downcast to an int. This patch introduces a new macro pte_isset which performs the bitwise and, then performs a double logical invert (where needed) to ensure predictable downcasting. The logical inverse pte_isclear is also introduced. Equivalent pmd functions for Transparent HugePages have also been added. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit f2950706871c4b6e8c0f0d7c3f62d35930b8de63 upstream.

Long descriptors on ARM are 64 bits, and some pte functions such as
pte_dirty return a bitwise-and of a flag with the pte value. If the
flag to be tested resides in the upper 32 bits of the pte, then we run
into the danger of the result being dropped if downcast.

For example:
	gather_stats(page, md, pte_dirty(*pte), 1);
where pte_dirty(*pte) is downcast to an int.

This patch introduces a new macro pte_isset which performs the bitwise
and, then performs a double logical invert (where needed) to ensure
predictable downcasting. The logical inverse pte_isclear is also
introduced.

Equivalent pmd functions for Transparent HugePages have also been
added.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 7931/1: Correct virt_addr_valid 2015-04-09T12:13:41+00:00 Laura Abbott lauraa@codeaurora.org 2013-12-21T00:03:06+00:00 eec585a2565ee1d56e92e1e80d612cd00ba05887 commit efea3403d4b7c6d1dd5d5ac3234c161e8b314d66 upstream. The definition of virt_addr_valid is that virt_addr_valid should return true if and only if virt_to_page returns a valid pointer. The current definition of virt_addr_valid only checks against the virtual address range. There's no guarantee that just because a virtual address falls bewteen PAGE_OFFSET and high_memory the associated physical memory has a valid backing struct page. Follow the example of other architectures and convert to pfn_valid to verify that the virtual address is actually valid. The check for an address between PAGE_OFFSET and high_memory is still necessary as vmalloc/highmem addresses are not valid with virt_to_page. Cc: Will Deacon <will.deacon@arm.com> Cc: Nicolas Pitre <nico@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit efea3403d4b7c6d1dd5d5ac3234c161e8b314d66 upstream.

The definition of virt_addr_valid is that virt_addr_valid should
return true if and only if virt_to_page returns a valid pointer.
The current definition of virt_addr_valid only checks against the
virtual address range. There's no guarantee that just because a
virtual address falls bewteen PAGE_OFFSET and high_memory the
associated physical memory has a valid backing struct page. Follow
the example of other architectures and convert to pfn_valid to
verify that the virtual address is actually valid. The check for
an address between PAGE_OFFSET and high_memory is still necessary
as vmalloc/highmem addresses are not valid with virt_to_page.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 7867/1: include: asm: use 'int' instead of 'unsigned long' for 'oldval' in atomic_cmpxchg(). 2015-04-09T12:13:41+00:00 Chen Gang gang.chen@asianux.com 2013-10-26T14:07:25+00:00 69f8bfe920fe43ea08fbd41dfdb5c0dad337ac46 commit 4dcc1cf7316a26e112f5c9fcca531ff98ef44700 upstream. For atomic_cmpxchg(), the type of 'oldval' need be 'int' to match the type of "*ptr" (used by 'ldrex' instruction) and 'old' (used by 'teq' instruction). Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 4dcc1cf7316a26e112f5c9fcca531ff98ef44700 upstream.

For atomic_cmpxchg(), the type of 'oldval' need be 'int' to match the
type of "*ptr" (used by 'ldrex' instruction) and 'old' (used by 'teq'
instruction).

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 7866/1: include: asm: use 'long long' instead of 'u64' within atomic.h 2015-04-09T12:13:40+00:00 Chen Gang gang.chen@asianux.com 2013-10-26T14:07:04+00:00 63448427542cdfbfcb1c84e1cfbbcef137bd4173 commit 237f12337cfa2175474e4dd015bc07a25eb9080d upstream. atomic* value is signed value, and atomic* functions need also process signed value (parameter value, and return value), so 32-bit arm need use 'long long' instead of 'u64'. After replacement, it will also fix a bug for atomic64_add_negative(): "u64 is never less than 0". The modifications are: in vim, use "1,% s/\<u64\>/long long/g" command. remove '__aligned(8)' which is useless for 64-bit. be sure of 80 column limitation after replacement. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 237f12337cfa2175474e4dd015bc07a25eb9080d upstream.

atomic* value is signed value, and atomic* functions need also process
signed value (parameter value, and return value), so 32-bit arm need
use 'long long' instead of 'u64'.

After replacement, it will also fix a bug for atomic64_add_negative():
"u64 is never less than 0".

The modifications are:

  in vim, use "1,% s/\<u64\>/long long/g" command.
  remove '__aligned(8)' which is useless for 64-bit.
  be sure of 80 column limitation after replacement.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: Correct BUG() assembly to ensure it is endian-agnostic 2015-04-09T12:13:37+00:00 Ben Dooks ben.dooks@codethink.co.uk 2013-07-25T13:38:03+00:00 c35d584129f4dcb1ef167427475e5452e456431e commit 63328070eff2f4fd730c86966a0dbc976147c39f upstream. Currently BUG() uses .word or .hword to create the necessary illegal instructions. However if we are building BE8 then these get swapped by the linker into different illegal instructions in the text. This means that the BUG() macro does not get trapped properly. Change to using <asm/opcodes.h> to provide the necessary ARM instruction building as we cannot rely on gcc/gas having the `.inst` instructions which where added to try and resolve this issue (reported by Dave Martin <Dave.Martin@arm.com>). Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 63328070eff2f4fd730c86966a0dbc976147c39f upstream.

Currently BUG() uses .word or .hword to create the necessary illegal
instructions. However if we are building BE8 then these get swapped
by the linker into different illegal instructions in the text. This
means that the BUG() macro does not get trapped properly.

Change to using <asm/opcodes.h> to provide the necessary ARM instruction
building as we cannot rely on gcc/gas having the `.inst` instructions
which where added to try and resolve this issue (reported by Dave Martin
<Dave.Martin@arm.com>).

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 8226/1: cacheflush: get rid of restarting block 2014-12-06T14:18:20+00:00 Vladimir Murzin vladimir.murzin@arm.com 2014-11-27T10:39:04+00:00 932307a475b5c56786987a98472c8e6c5bb5cd78 commit 3f4aa45ceea5789a4aade536acc27f2e0d3da5e1 upstream. We cannot restart cacheflush safely if a process provides user-defined signal handler and signal is pending. In this case -EINTR is returned and it is expected that process re-invokes syscall. However, there are a few problems with that: * looks like nobody bothers checking return value from cacheflush * but if it did, we don't provide the restart address for that, so the process has to use the same range again * ...and again, what might lead to looping forever So, remove cacheflush restarting code and terminate cache flushing as early as fatal signal is pending. Reported-by: Chanho Min <chanho.min@lge.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 3f4aa45ceea5789a4aade536acc27f2e0d3da5e1 upstream.

We cannot restart cacheflush safely if a process provides user-defined
signal handler and signal is pending. In this case -EINTR is returned
and it is expected that process re-invokes syscall. However, there are
a few problems with that:
 * looks like nobody bothers checking return value from cacheflush
 * but if it did, we don't provide the restart address for that, so the
   process has to use the same range again
 * ...and again, what might lead to looping forever

So, remove cacheflush restarting code and terminate cache flushing
as early as fatal signal is pending.

Reported-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 8148/1: flush TLS and thumbee register state during exec 2014-10-13T13:41:07+00:00 Nathan Lynch nathan_lynch@mentor.com 2014-09-11T01:49:08+00:00 3443c6fd1de2485cbd3e94ac35e54586a8ecc69f commit fbfb872f5f417cea48760c535e0ff027c88b507a upstream. The TPIDRURO and TPIDRURW registers need to be flushed during exec; otherwise TLS information is potentially leaked. TPIDRURO in particular needs careful treatment. Since flush_thread basically needs the same code used to set the TLS in arm_syscall, pull that into a common set_tls helper in tls.h and use it in both places. Similarly, TEEHBR needs to be cleared during exec as well. Clearing its save slot in thread_info isn't right as there is no guarantee that a thread switch will occur before the new program runs. Just setting the register directly is sufficient. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit fbfb872f5f417cea48760c535e0ff027c88b507a upstream.

The TPIDRURO and TPIDRURW registers need to be flushed during exec;
otherwise TLS information is potentially leaked.  TPIDRURO in
particular needs careful treatment.  Since flush_thread basically
needs the same code used to set the TLS in arm_syscall, pull that into
a common set_tls helper in tls.h and use it in both places.

Similarly, TEEHBR needs to be cleared during exec as well.  Clearing
its save slot in thread_info isn't right as there is no guarantee
that a thread switch will occur before the new program runs.  Just
setting the register directly is sufficient.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 8051/1: put_user: fix possible data corruption in put_user 2014-06-20T15:33:59+00:00 Andrey Ryabinin a.ryabinin@samsung.com 2014-05-07T07:07:25+00:00 add232a1a6031431736e0c774cb8e1e7fe89db60 commit 537094b64b229bf3ad146042f83e74cf6abe59df upstream. According to arm procedure call standart r2 register is call-cloberred. So after the result of x expression was put into r2 any following function call in p may overwrite r2. To fix this, the result of p expression must be saved to the temporary variable before the assigment x expression to __r2. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 537094b64b229bf3ad146042f83e74cf6abe59df upstream.

According to arm procedure call standart r2 register is call-cloberred.
So after the result of x expression was put into r2 any following
function call in p may overwrite r2. To fix this, the result of p
expression must be saved to the temporary variable before the
assigment x expression to __r2.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARM: 8027/1: fix do_div() bug in big-endian systems 2014-05-15T07:54:44+00:00 Xiangyu Lu luxiangyu@huawei.com 2014-04-15T08:38:17+00:00 b988548f6a507b2240b27aeb61685336d43acb4b commit 80bb3ef109ff40a7593d9481c17de9bbc4d7c0e2 upstream. In big-endian systems, "%1" get the most significant part of the value, cause the instruction to get the wrong result. When viewing ftrace record in big-endian ARM systems, we found that the timestamp errors: swapper-0 [001] 1325.970000: 0:120:R ==> [001] 16:120:R events/1 events/1-16 [001] 1325.970000: 16:120:S ==> [001] 0:120:R swapper swapper-0 [000] 1325.1000000: 0:120:R + [000] 15:120:R events/0 swapper-0 [000] 1325.1000000: 0:120:R ==> [000] 15:120:R events/0 swapper-0 [000] 1326.030000: 0:120:R + [000] 1150:120:R sshd swapper-0 [000] 1326.030000: 0:120:R ==> [000] 1150:120:R sshd When viewed ftrace records, it will call the do_div(n, base) function, which achieved arch/arm/include/asm/div64.h in. When n = 10000000, base = 1000000, in do_div(n, base) will execute "umull %Q0, %R0, %1, %Q2". Reviewed-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Alex Wu <wuquanming@huawei.com> Signed-off-by: Xiangyu Lu <luxiangyu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 80bb3ef109ff40a7593d9481c17de9bbc4d7c0e2 upstream.

In big-endian systems, "%1" get the most significant part of the value, cause the instruction to get the wrong result.

When viewing ftrace record in big-endian ARM systems, we found that
the timestamp errors:

swapper-0   [001] 1325.970000:   0:120:R ==> [001]    16:120:R events/1
events/1-16 [001] 1325.970000:   16:120:S ==> [001]    0:120:R swapper
swapper-0   [000] 1325.1000000:  0:120:R   + [000]    15:120:R events/0
swapper-0   [000] 1325.1000000:  0:120:R ==> [000]    15:120:R events/0
swapper-0   [000] 1326.030000:   0:120:R   + [000]  1150:120:R sshd
swapper-0   [000] 1326.030000:   0:120:R ==> [000]  1150:120:R sshd

When viewed ftrace records, it will call the do_div(n, base) function, which achieved arch/arm/include/asm/div64.h in. When n = 10000000, base = 1000000, in do_div(n, base) will execute "umull %Q0, %R0, %1, %Q2".

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Alex Wu <wuquanming@huawei.com>
Signed-off-by: Xiangyu Lu <luxiangyu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>