linux-stable.git/arch/arm/kernel, branch linux-3.4.y Linux kernel stable tree ARM: fix Thumb2 signal handling when ARMv6 is enabled 2016-04-27T10:55:19+00:00 Russell King rmk+kernel@arm.linux.org.uk 2015-09-11T15:44:02+00:00 31a526445157a00b43d5018b1fdc2b8aa6c84c78 commit 9b55613f42e8d40d5c9ccb8970bde6af4764b2ab upstream. When a kernel is built covering ARMv6 to ARMv7, we omit to clear the IT state when entering a signal handler. This can cause the first few instructions to be conditionally executed depending on the parent context. In any case, the original test for >= ARMv7 is broken - ARMv6 can have Thumb-2 support as well, and an ARMv6T2 specific build would omit this code too. Relax the test back to ARMv6 or greater. This results in us always clearing the IT state bits in the PSR, even on CPUs where these bits are reserved. However, they're reserved for the IT state, so this should cause no harm. Fixes: d71e1352e240 ("Clear the IT state when invoking a Thumb-2 signal handler") Acked-by: Tony Lindgren <tony@atomide.com> Tested-by: H. Nikolaus Schaller <hns@goldelico.com> Tested-by: Grazvydas Ignotas <notasas@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Zefan Li <lizefan@huawei.com> 
commit 9b55613f42e8d40d5c9ccb8970bde6af4764b2ab upstream.

When a kernel is built covering ARMv6 to ARMv7, we omit to clear the
IT state when entering a signal handler.  This can cause the first
few instructions to be conditionally executed depending on the parent
context.

In any case, the original test for >= ARMv7 is broken - ARMv6 can have
Thumb-2 support as well, and an ARMv6T2 specific build would omit this
code too.

Relax the test back to ARMv6 or greater.  This results in us always
clearing the IT state bits in the PSR, even on CPUs where these bits
are reserved.  However, they're reserved for the IT state, so this
should cause no harm.

Fixes: d71e1352e240 ("Clear the IT state when invoking a Thumb-2 signal handler")
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Zefan Li <lizefan@huawei.com>
ARM: 7880/1: Clear the IT state independent of the Thumb-2 mode 2016-04-27T10:55:19+00:00 T.J. Purtell tj@mobisocial.us 2013-11-06T17:38:05+00:00 b2e30785526c7e1b7bba74d5c50784cfcfe0bc21 commit 6ecf830e5029598732e04067e325d946097519cb upstream. The ARM architecture reference specifies that the IT state bits in the PSR must be all zeros in ARM mode or behavior is unspecified. On the Qualcomm Snapdragon S4/Krait architecture CPUs the processor continues to consider the IT state bits while in ARM mode. This makes it so that some instructions are skipped by the CPU. Signed-off-by: T.J. Purtell <tj@mobisocial.us> [rmk+kernel@arm.linux.org.uk: fixed whitespace formatting in patch] Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Zefan Li <lizefan@huawei.com> 
commit 6ecf830e5029598732e04067e325d946097519cb upstream.

The ARM architecture reference specifies that the IT state bits in the
PSR must be all zeros in ARM mode or behavior is unspecified.  On the
Qualcomm Snapdragon S4/Krait architecture CPUs the processor continues
to consider the IT state bits while in ARM mode.  This makes it so
that some instructions are skipped by the CPU.

Signed-off-by: T.J. Purtell <tj@mobisocial.us>
[rmk+kernel@arm.linux.org.uk: fixed whitespace formatting in patch]
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Zefan Li <lizefan@huawei.com>
ARM: 8129/1: errata: work around Cortex-A15 erratum 830321 using dummy strex 2014-09-25T03:49:16+00:00 Mark Rutland mark.rutland@arm.com 2014-08-15T11:11:50+00:00 2f3e285da53ae6002cabb028438a65b9f9cee534 commit 2c32c65e3726c773760038910be30cce1b4d4149 upstream. On revisions of Cortex-A15 prior to r3p3, a CLREX instruction at PL1 may falsely trigger a watchpoint exception, leading to potential data aborts during exception return and/or livelock. This patch resolves the issue in the following ways: - Replacing our uses of CLREX with a dummy STREX sequence instead (as we did for v6 CPUs). - Removing the clrex code from v7_exit_coherency_flush and derivatives, since this only exists as a minor performance improvement when non-cached exclusives are in use (Linux doesn't use these). Benchmarking on a variety of ARM cores revealed no measurable performance difference with this change applied, so the change is performed unconditionally and no new Kconfig entry is added. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [lizf: Backported to 3.4: - Drop changes to arch/arm/include/asm/cacheflush.h and arch/arm/mach-exynos/mcpm-exynos.c] Signed-off-by: Zefan Li <lizefan@huawei.com> 
commit 2c32c65e3726c773760038910be30cce1b4d4149 upstream.

On revisions of Cortex-A15 prior to r3p3, a CLREX instruction at PL1 may
falsely trigger a watchpoint exception, leading to potential data aborts
during exception return and/or livelock.

This patch resolves the issue in the following ways:

  - Replacing our uses of CLREX with a dummy STREX sequence instead (as
    we did for v6 CPUs).

  - Removing the clrex code from v7_exit_coherency_flush and derivatives,
    since this only exists as a minor performance improvement when
    non-cached exclusives are in use (Linux doesn't use these).

Benchmarking on a variety of ARM cores revealed no measurable
performance difference with this change applied, so the change is
performed unconditionally and no new Kconfig entry is added.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[lizf: Backported to 3.4:
 - Drop changes to arch/arm/include/asm/cacheflush.h and
   arch/arm/mach-exynos/mcpm-exynos.c]
Signed-off-by: Zefan Li <lizefan@huawei.com>
ARM: stacktrace: avoid listing stacktrace functions in stacktrace 2014-07-01T03:01:33+00:00 Russell King rmk+kernel@arm.linux.org.uk 2014-05-03T10:03:28+00:00 b2ff2f48d169e743dd074ca53a6fb1c295771254 commit 3683f44c42e991d313dc301504ee0fca1aeb8580 upstream. While debugging the FEC ethernet driver using stacktrace, it was noticed that the stacktraces always begin as follows: [<c00117b4>] save_stack_trace_tsk+0x0/0x98 [<c0011870>] save_stack_trace+0x24/0x28 ... This is because the stack trace code includes the stack frames for itself. This is incorrect behaviour, and also leads to "skip" doing the wrong thing (which is the number of stack frames to avoid recording.) Perversely, it does the right thing when passed a non-current thread. Fix this by ensuring that we have a known constant number of frames above the main stack trace function, and always skip these. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3683f44c42e991d313dc301504ee0fca1aeb8580 upstream.

While debugging the FEC ethernet driver using stacktrace, it was noticed
that the stacktraces always begin as follows:

 [<c00117b4>] save_stack_trace_tsk+0x0/0x98
 [<c0011870>] save_stack_trace+0x24/0x28
 ...

This is because the stack trace code includes the stack frames for itself.
This is incorrect behaviour, and also leads to "skip" doing the wrong
thing (which is the number of stack frames to avoid recording.)

Perversely, it does the right thing when passed a non-current thread.  Fix
this by ensuring that we have a known constant number of frames above the
main stack trace function, and always skip these.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 8012/1: kdump: Avoid overflow when converting pfn to physaddr 2014-06-07T23:02:02+00:00 Liu Hua sdu.liu@huawei.com 2014-03-27T05:56:18+00:00 3b2437c2a0316013a52cfa55c0486aafe5b94f77 commit 8fad87bca7ac9737e413ba5f1656f1114a8c314d upstream. When we configure CONFIG_ARM_LPAE=y, pfn << PAGE_SHIFT will overflow if pfn >= 0x100000 in copy_oldmem_page. So use __pfn_to_phys for converting. Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8fad87bca7ac9737e413ba5f1656f1114a8c314d upstream.

When we configure CONFIG_ARM_LPAE=y, pfn << PAGE_SHIFT will
overflow if pfn >= 0x100000 in copy_oldmem_page.
So use __pfn_to_phys for converting.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 8030/1: ARM : kdump : add arch_crash_save_vmcoreinfo 2014-05-06T14:51:40+00:00 Liu Hua sdu.liu@huawei.com 2014-04-18T06:45:36+00:00 61d0294719523889c7ce32d33a2ab7cc73fbb814 commit 56b700fd6f1e49149880fb1b6ffee0dca5be45fb upstream. For vmcore generated by LPAE enabled kernel, user space utility such as crash needs additional infomation to parse. So this patch add arch_crash_save_vmcoreinfo as what PAE enabled i386 linux does. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 56b700fd6f1e49149880fb1b6ffee0dca5be45fb upstream.

For vmcore generated by LPAE enabled kernel, user space
utility such as crash needs additional infomation to
parse.

So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
i386 linux does.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 7628/1: head.S: map one extra section for the ATAG/DTB area 2014-04-14T13:44:21+00:00 Nicolas Pitre nicolas.pitre@linaro.org 2013-01-15T17:51:32+00:00 f3e650df41db32aeb319d4531cc9df6fba4e3c9a commit 6f16f4998f98e42e3f2dedf663cfb691ff0324af upstream. We currently use a temporary 1MB section aligned to a 1MB boundary for mapping the provided device tree until the final page table is created. However, if the device tree happens to cross that 1MB boundary, the end of it remains unmapped and the kernel crashes when it attempts to access it. Given no restriction on the location of that DTB, it could end up with only a few bytes mapped at the end of a section. Solve this issue by mapping two consecutive sections. Signed-off-by: Nicolas Pitre <nico@linaro.org> Tested-by: Sascha Hauer <s.hauer@pengutronix.de> Tested-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [bwh: Backported to 3.2: - Adjust context - The mapping is not conditional; drop the 'ne' suffixes] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> [yangyl: Backported to 3.4: Adjust context] Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6f16f4998f98e42e3f2dedf663cfb691ff0324af upstream.

We currently use a temporary 1MB section aligned to a 1MB boundary for
mapping the provided device tree until the final page table is created.
However, if the device tree happens to cross that 1MB boundary, the end
of it remains unmapped and the kernel crashes when it attempts to access
it.  Given no restriction on the location of that DTB, it could end up
with only a few bytes mapped at the end of a section.

Solve this issue by mapping two consecutive sections.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
 - Adjust context
 - The mapping is not conditional; drop the 'ne' suffixes]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[yangyl: Backported to 3.4: Adjust context]
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 7742/1: topology: export cpu_topology 2014-04-14T13:44:20+00:00 Arnd Bergmann arnd@arndb.de 2013-05-31T21:49:22+00:00 c9925863935ad8bb5f575224849b2d5d173c4dd1 commit 92bdd3f5eba299b33c2f4407977d6fa2e2a6a0da upstream. The cpu_topology symbol is required by any driver using the topology interfaces, which leads to a couple of build errors: ERROR: "cpu_topology" [drivers/net/ethernet/sfc/sfc.ko] undefined! ERROR: "cpu_topology" [drivers/cpufreq/arm_big_little.ko] undefined! ERROR: "cpu_topology" [drivers/block/mtip32xx/mtip32xx.ko] undefined! The obvious solution is to export this symbol. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 92bdd3f5eba299b33c2f4407977d6fa2e2a6a0da upstream.

The cpu_topology symbol is required by any driver using the topology
interfaces, which leads to a couple of build errors:

ERROR: "cpu_topology" [drivers/net/ethernet/sfc/sfc.ko] undefined!
ERROR: "cpu_topology" [drivers/cpufreq/arm_big_little.ko] undefined!
ERROR: "cpu_topology" [drivers/block/mtip32xx/mtip32xx.ko] undefined!

The obvious solution is to export this symbol.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: fix "bad mode in ... handler" message for undefined instructions 2014-01-15T23:27:11+00:00 Russell King rmk+kernel@arm.linux.org.uk 2014-01-03T15:01:39+00:00 10252aa2278e1d53c420bacdf9ee239784712541 commit 29c350bf28da333e41e30497b649fe335712a2ab upstream. The array was missing the final entry for the undefined instruction exception handler; this commit adds it. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 29c350bf28da333e41e30497b649fe335712a2ab upstream.

The array was missing the final entry for the undefined instruction
exception handler; this commit adds it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: 7913/1: fix framepointer check in unwind_frame 2013-12-20T15:34:19+00:00 Konstantin Khlebnikov k.khlebnikov@samsung.com 2013-12-05T13:23:48+00:00 47131c7c78b82c3b67020ee99834841ec6f096b5 commit 3abb6671a9c04479c4bd026798a05f857393b7e2 upstream. This patch fixes corner case when (fp + 4) overflows unsigned long, for example: fp = 0xFFFFFFFF -> fp + 4 == 3. Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3abb6671a9c04479c4bd026798a05f857393b7e2 upstream.

This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -> fp + 4 == 3.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>