linux-stable.git/arch/arm, branch v3.4.104 Linux kernel stable tree 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: 8128/1: abort: don't clear the exclusive monitors 2014-09-25T03:49:16+00:00 Mark Rutland mark.rutland@arm.com 2014-08-15T11:11:49+00:00 5624bb35686b13e17438aaf211586556bcba58da commit 85868313177700d20644263a782351262d2aff84 upstream. The ARMv6 and ARMv7 early abort handlers clear the exclusive monitors upon entry to the kernel, but this is redundant: - We clear the monitors on every exception return since commit 200b812d0084 ("Clear the exclusive monitor when returning from an exception"), so this is not necessary to ensure the monitors are cleared before returning from a fault handler. - Any dummy STREX will target a temporary scratch area in memory, and may succeed or fail without corrupting useful data. Its status value will not be used. - Any other STREX in the kernel must be preceded by an LDREX, which will initialise the monitors consistently and will not depend on the earlier state of the monitors. Therefore we have no reason to care about the initial state of the exclusive monitors when a data abort is taken, and clearing the monitors prior to exception return (as we already do) is sufficient. This patch removes the redundant clearing of the exclusive monitors from the early abort handlers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Zefan Li <lizefan@huawei.com> 
commit 85868313177700d20644263a782351262d2aff84 upstream.

The ARMv6 and ARMv7 early abort handlers clear the exclusive monitors
upon entry to the kernel, but this is redundant:

  - We clear the monitors on every exception return since commit
    200b812d0084 ("Clear the exclusive monitor when returning from an
    exception"), so this is not necessary to ensure the monitors are
    cleared before returning from a fault handler.

  - Any dummy STREX will target a temporary scratch area in memory, and
    may succeed or fail without corrupting useful data. Its status value
    will not be used.

  - Any other STREX in the kernel must be preceded by an LDREX, which
    will initialise the monitors consistently and will not depend on the
    earlier state of the monitors.

Therefore we have no reason to care about the initial state of the
exclusive monitors when a data abort is taken, and clearing the monitors
prior to exception return (as we already do) is sufficient.

This patch removes the redundant clearing of the exclusive monitors from
the early abort handlers.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Zefan Li <lizefan@huawei.com>
ARM: 8115/1: LPAE: reduce damage caused by idmap to virtual memory layout 2014-08-07T19:00:10+00:00 Konstantin Khlebnikov k.khlebnikov@samsung.com 2014-07-25T08:17:12+00:00 2e926a6b962cfc154818fd0796c4815df6ed09d0 commit 811a2407a3cf7bbd027fbe92d73416f17485a3d8 upstream. On LPAE, each level 1 (pgd) page table entry maps 1GiB, and the level 2 (pmd) entries map 2MiB. When the identity mapping is created on LPAE, the pgd pointers are copied from the swapper_pg_dir. If we find that we need to modify the contents of a pmd, we allocate a new empty pmd table and insert it into the appropriate 1GB slot, before then filling it with the identity mapping. However, if the 1GB slot covers the kernel lowmem mappings, we obliterate those mappings. When replacing a PMD, first copy the old PMD contents to the new PMD, so that we preserve the existing mappings, particularly the mappings of the kernel itself. [rewrote commit message and added code comment -- rmk] Fixes: ae2de101739c ("ARM: LPAE: Add identity mapping support for the 3-level page table format") 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 811a2407a3cf7bbd027fbe92d73416f17485a3d8 upstream.

On LPAE, each level 1 (pgd) page table entry maps 1GiB, and the level 2
(pmd) entries map 2MiB.

When the identity mapping is created on LPAE, the pgd pointers are copied
from the swapper_pg_dir.  If we find that we need to modify the contents
of a pmd, we allocate a new empty pmd table and insert it into the
appropriate 1GB slot, before then filling it with the identity mapping.

However, if the 1GB slot covers the kernel lowmem mappings, we obliterate
those mappings.

When replacing a PMD, first copy the old PMD contents to the new PMD, so
that we preserve the existing mappings, particularly the mappings of the
kernel itself.

[rewrote commit message and added code comment -- rmk]

Fixes: ae2de101739c ("ARM: LPAE: Add identity mapping support for the 3-level page table format")
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>
ARM: OMAP2+: Fix parser-bug in platform muxing code 2014-07-09T17:51:20+00:00 David R. Piegdon lkml@p23q.org 2014-06-16T23:42:51+00:00 ba8f03aa4a5aced02df87e69737922eeb14a7350 commit c021f241f4fab2bb4fc4120a38a828a03dd3f970 upstream. Fix a parser-bug in the omap2 muxing code where muxtable-entries will be wrongly selected if the requested muxname is a *prefix* of their m0-entry and they have a matching mN-entry. Fix by additionally checking that the length of the m0_entry is equal. For example muxing of "dss_data2.dss_data2" on omap32xx will fail because the prefix "dss_data2" will match the mux-entries "dss_data2" as well as "dss_data20", with the suffix "dss_data2" matching m0 (for dss_data2) and m4 (for dss_data20). Thus both are recognized as signal path candidates: Relevant muxentries from mux34xx.c: _OMAP3_MUXENTRY(DSS_DATA20, 90, "dss_data20", NULL, "mcspi3_somi", "dss_data2", "gpio_90", NULL, NULL, "safe_mode"), _OMAP3_MUXENTRY(DSS_DATA2, 72, "dss_data2", NULL, NULL, NULL, "gpio_72", NULL, NULL, "safe_mode"), This will result in a failure to mux the pin at all: _omap_mux_get_by_name: Multiple signal paths (2) for dss_data2.dss_data2 Patch should apply to linus' latest master down to rather old linux-2.6 trees. Signed-off-by: David R. Piegdon <lkml@p23q.org> Cc: stable@vger.kernel.org [tony@atomide.com: updated description to include full description] Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c021f241f4fab2bb4fc4120a38a828a03dd3f970 upstream.

Fix a parser-bug in the omap2 muxing code where muxtable-entries will be
wrongly selected if the requested muxname is a *prefix* of their
m0-entry and they have a matching mN-entry. Fix by additionally checking
that the length of the m0_entry is equal.

For example muxing of "dss_data2.dss_data2" on omap32xx will fail
because the prefix "dss_data2" will match the mux-entries "dss_data2" as
well as "dss_data20", with the suffix "dss_data2" matching m0 (for
dss_data2) and m4 (for dss_data20). Thus both are recognized as signal
path candidates:

Relevant muxentries from mux34xx.c:
        _OMAP3_MUXENTRY(DSS_DATA20, 90,
                "dss_data20", NULL, "mcspi3_somi", "dss_data2",
                "gpio_90", NULL, NULL, "safe_mode"),
        _OMAP3_MUXENTRY(DSS_DATA2, 72,
                "dss_data2", NULL, NULL, NULL,
                "gpio_72", NULL, NULL, "safe_mode"),

This will result in a failure to mux the pin at all:

 _omap_mux_get_by_name: Multiple signal paths (2) for dss_data2.dss_data2

Patch should apply to linus' latest master down to rather old linux-2.6
trees.

Signed-off-by: David R. Piegdon <lkml@p23q.org>
Cc: stable@vger.kernel.org
[tony@atomide.com: updated description to include full description]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: 8051/1: put_user: fix possible data corruption in put_user 2014-06-11T19:04:11+00:00 Andrey Ryabinin a.ryabinin@samsung.com 2014-05-07T07:07:25+00:00 ee40d72c3e6fc7e6cd5241eb84fa104b61dc8ec3 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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: 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: 8027/1: fix do_div() bug in big-endian systems 2014-05-06T14:51:40+00:00 Xiangyu Lu luxiangyu@huawei.com 2014-04-15T08:38:17+00:00 76ff67ac5a2585634709abc41a0a9f3f3b28c90f 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: OMAP3: hwmod data: Correct clock domains for USB modules 2014-05-06T14:51:40+00:00 Roger Quadros rogerq@ti.com 2014-04-10T07:18:17+00:00 375f0dfa0c993b38ca4cd6f5859cc2a35ee10157 commit c6c56697ae4bf1226263c19e8353343d7083f40e upstream. OMAP3 doesn't contain "l3_init_clkdm" clock domain. Use the proper clock domains for USB Host and USB TLL modules. Gets rid of the following warnings during boot omap_hwmod: usb_host_hs: could not associate to clkdm l3_init_clkdm omap_hwmod: usb_tll_hs: could not associate to clkdm l3_init_clkdm Reported-by: Nishanth Menon <nm@ti.com> Cc: Paul Walmsley <paul@pwsan.com> Signed-off-by: Roger Quadros <rogerq@ti.com> Fixes: de231388cb80a8ef3e779bbfa0564ba0157b7377 ("ARM: OMAP: USB: EHCI and OHCI hwmod structures for OMAP3") Cc: Keshava Munegowda <keshava_mgowda@ti.com> Cc: Partha Basak <parthab@india.ti.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c6c56697ae4bf1226263c19e8353343d7083f40e upstream.

OMAP3 doesn't contain "l3_init_clkdm" clock domain. Use the
proper clock domains for USB Host and USB TLL modules.

Gets rid of the following warnings during boot
 omap_hwmod: usb_host_hs: could not associate to clkdm l3_init_clkdm
 omap_hwmod: usb_tll_hs: could not associate to clkdm l3_init_clkdm

Reported-by: Nishanth Menon <nm@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Fixes: de231388cb80a8ef3e779bbfa0564ba0157b7377 ("ARM: OMAP: USB: EHCI and OHCI hwmod structures for OMAP3")
Cc: Keshava Munegowda <keshava_mgowda@ti.com>
Cc: Partha Basak <parthab@india.ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>