commit 5e4ba617c1b584b2e376f31a63bd4e734109318a upstream.
Martin Storsjö reports that the sequence:
ee312ac1 vsub.f32 s4, s3, s2
ee702ac0 vsub.f32 s5, s1, s0
e59f0028 ldr r0, [pc, #40]
ee111a90 vmov r1, s3
on Raspberry Pi (implementor 41 architecture 1 part 20 variant b rev 5)
where s3 is a denormal and s2 is zero results in incorrect behaviour -
the instruction "vsub.f32 s5, s1, s0" is not executed:
VFP: bounce: trigger ee111a90 fpexc d0000780
VFP: emulate: INST=0xee312ac1 SCR=0x00000000
...
As we can see, the instruction triggering the exception is the "vmov"
instruction, and we emulate the "vsub.f32 s4, s3, s2" but fail to
properly take account of the FPEXC_FP2V flag in FPEXC. This is because
the test for the second instruction register being valid is bogus, and
will always skip emulation of the second instruction.
Reported-by: Martin Storsjö <martin@martin.st>
Tested-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 39141ddfb63a664f26d3f42f64ee386e879b492c upstream.
After commit 846a136881b8f73c1f74250bf6acfaa309cab1f2 ("ARM: vfp: fix
saving d16-d31 vfp registers on v6+ kernels"), the OMAP 2430SDP board
started crashing during boot with omap2plus_defconfig:
[ 3.875122] mmcblk0: mmc0:e624 SD04G 3.69 GiB
[ 3.915954] mmcblk0: p1
[ 4.086639] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
[ 4.093719] Modules linked in:
[ 4.096954] CPU: 0 Not tainted (3.6.0-02232-g759e00b #570)
[ 4.103149] PC is at vfp_reload_hw+0x1c/0x44
[ 4.107666] LR is at __und_usr_fault_32+0x0/0x8
It turns out that the context save/restore fix unmasked a latent bug
in commit 5aaf254409f8d58229107b59507a8235b715a960 ("ARM: 6203/1: Make
VFPv3 usable on ARMv6"). When CONFIG_VFPv3 is set, but the kernel is
booted on a pre-VFPv3 core, the code attempts to save and restore the
d16-d31 VFP registers. These are only present on non-D16 VFPv3+, so
this results in an undefined instruction exception. The code didn't
crash before commit 846a136 because the save and restore code was
only touching d0-d15, present on all VFP.
Fix by implementing a request from Russell King to add a new HWCAP
flag that affirmatively indicates the presence of the d16-d31
registers:
http://marc.info/?l=linux-arm-kernel&m=135013547905283&w=2
and some feedback from Måns to clarify the name of the HWCAP flag.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@linaro.org>
Cc: Måns Rullgård <mans.rullgard@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert some ARM architecture's common code to using struct syscore_ops objects for power management instead of sysdev classes and sysdevs. This simplifies the code and reduces the kernel's memory footprint. It also is necessary for removing sysdevs from the kernel entirely in the future. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
VFP registers d16-d31 are callee saved registers and must be preserved during function calls, including fork(). The VFP configuration should also be preserved. The patch copies the full VFP state to the child process. Reported-by: Paul Wright <paul.wright@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds THREAD_NOTIFY_COPY for calling registered handlers during the copy_thread() function call. It also changes the VFP handler to use a switch statement rather than if..else and ignore this event. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (25 commits) video: change to new flag variable scsi: change to new flag variable rtc: change to new flag variable rapidio: change to new flag variable pps: change to new flag variable net: change to new flag variable misc: change to new flag variable message: change to new flag variable memstick: change to new flag variable isdn: change to new flag variable ieee802154: change to new flag variable ide: change to new flag variable hwmon: change to new flag variable dma: change to new flag variable char: change to new flag variable fs: change to new flag variable xtensa: change to new flag variable um: change to new flag variables s390: change to new flag variable mips: change to new flag variable ... Fix up trivial conflict in drivers/hwmon/Makefile
Replace EXTRA_CFLAGS with ccflags-y and EXTRA_AFLAGS with asflags-y. Signed-off-by: matt mooney <mfm@muteddisk.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
Improve the documentation for the VFP hotplug notifier handler, so that people better understand what's going on there and what has been done for them. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/return_address.c:37:6: warning: symbol 'return_address' was not declared. Should it be static? arch/arm/kernel/setup.c:76:14: warning: symbol 'processor_id' was not declared. Should it be static? arch/arm/kernel/traps.c:259:1: warning: symbol 'die_lock' was not declared. Should it be static? arch/arm/vfp/vfpmodule.c:156:6: warning: symbol 'vfp_raise_sigfpe' was not declared. Should it be static? Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Conflicts: arch/arm/Kconfig arch/arm/common/Makefile arch/arm/kernel/Makefile arch/arm/kernel/smp.c