linux/arch/arm
Paul Walmsley 39141ddfb6 ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set
After commit 846a136881 ("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 5aaf254409 ("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>
2012-10-29 10:04:05 +00:00
..
boot Merge tag 'fixes-for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc into fixes 2012-10-22 22:56:09 +01:00
common ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
configs UAPI Disintegration 2012-10-09 2012-10-09 15:04:25 +01:00
crypto
include ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set 2012-10-29 10:04:05 +00:00
kernel ARM: 7565/1: sched: stop sched_clock() during suspend 2012-10-29 10:02:49 +00:00
lib ARM: export default read_current_timer 2012-10-09 20:24:36 +02:00
mach-at91 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-bcm2835 ARM: dtb: move all dtb targets to common Makefile 2012-09-20 22:58:17 -07:00
mach-clps711x ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-cns3xxx
mach-davinci ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-dove Merge branch 'samsung_platform_data' into staging/for_v3.7 2012-10-05 22:32:05 -03:00
mach-ebsa110 ARM: soc: driver specific changes 2012-10-01 18:46:13 -07:00
mach-ep93xx ARM: soc: multiplatform enablement 2012-10-01 19:11:38 -07:00
mach-exynos ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-footbridge ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-gemini
mach-h720x ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-highbank Merge branch 'for-v3.7' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping 2012-10-02 19:13:12 -07:00
mach-imx ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-integrator ARM: integrator: use __iomem pointers for MMIO, part 2 2012-10-09 17:27:33 +02:00
mach-iop13xx Merge branch 'late/fixes' into fixes 2012-10-07 07:22:32 -07:00
mach-iop32x Merge branch 'cleanup/__iomem' into next/cleanup 2012-09-22 10:24:29 -07:00
mach-iop33x
mach-ixp4xx ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-kirkwood Merge branch 'samsung_platform_data' into staging/for_v3.7 2012-10-05 22:32:05 -03:00
mach-ks8695 Merge branch 'late/fixes' into fixes 2012-10-07 07:22:32 -07:00
mach-l7200/include/mach
mach-lpc32xx ARM: soc: multiplatform enablement 2012-10-01 19:11:38 -07:00
mach-mmp ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-msm ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-mv78xx0 Merge branch 'late/fixes' into fixes 2012-10-07 07:22:32 -07:00
mach-mvebu ARM: mvebu: fix build breaks from multi-platform conversion 2012-09-28 22:27:07 +02:00
mach-mxs ARM: soc: multiplatform enablement 2012-10-01 19:11:38 -07:00
mach-netx ARM: netx: move platform_data definitions 2012-09-14 11:17:36 +02:00
mach-nomadik ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-omap1 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-omap2 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-orion5x ARM: soc: late platform updates 2012-10-07 20:55:16 +09:00
mach-picoxcell ARM: initial multiplatform support 2012-09-14 09:22:06 -05:00
mach-prima2 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-pxa ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-realview ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-rpc ARM: rpc: check device_register return code in ecard_probe 2012-10-07 10:33:09 +02:00
mach-s3c24xx ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s3c64xx ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s3c2410
mach-s3c2412 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s3c2440 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s5p64x0 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s5pc100 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-s5pv210 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-sa1100 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-shark Merge branch 'late/fixes' into fixes 2012-10-07 07:22:32 -07:00
mach-shmobile ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-socfpga ARM: initial multiplatform support 2012-09-14 09:22:06 -05:00
mach-spear3xx ARM: move all dtb targets out of Makefile.boot 2012-09-14 09:22:04 -05:00
mach-spear6xx ARM: move all dtb targets out of Makefile.boot 2012-09-14 09:22:04 -05:00
mach-spear13xx Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-10-10 11:10:41 +09:00
mach-tegra ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-u300 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-ux500 ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-versatile ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
mach-vexpress Features: 2012-10-07 07:13:01 +09:00
mach-vt8500 arm: vt8500: Fix build warning in uncompress.h 2012-10-07 14:50:06 -07:00
mach-w90x900 ARM: w90x900: move platform_data definitions 2012-09-14 11:18:59 +02:00
mach-zynq
mm Merge tag 'fixes-for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc into fixes 2012-10-22 22:56:09 +01:00
net
nwfpe
oprofile
plat-iop
plat-mxc ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-nomadik ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-omap ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-orion Merge branch 'samsung_platform_data' into staging/for_v3.7 2012-10-05 22:32:05 -03:00
plat-pxa ARM: pxa: move platform_data definitions 2012-09-14 11:18:10 +02:00
plat-s3c24xx ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-samsung ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-spear ARM: config: sort select statements alphanumerically 2012-10-13 17:11:28 +01:00
plat-versatile Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-10-07 21:20:57 +09:00
tools ARM: be really quiet when building with 'make -s' 2012-10-09 20:29:05 +02:00
vfp ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set 2012-10-29 10:04:05 +00:00
xen
Kconfig Merge tag 'fixes-for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc into fixes 2012-10-22 22:56:09 +01:00
Kconfig-nommu
Kconfig.debug ARM: soc: multiplatform enablement 2012-10-01 19:11:38 -07:00
Makefile ARM: pass -marm to gcc by default for both C and assembler 2012-10-09 20:29:05 +02:00