kernel_samsung_sm7125

jenna

History

Ivan Djelic 455bd4c430 ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) optimizations Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on assumptions about the implementation of memset and similar functions. The current ARM optimized memset code does not return the value of its first argument, as is usually expected from standard implementations. For instance in the following function: void debug_mutex_lock_common(struct mutex lock, struct mutex_waiter waiter) { memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); waiter->magic = waiter; INIT_LIST_HEAD(&waiter->list); } compiled as: 800554d0 <debug_mutex_lock_common>: 800554d0: e92d4008 push {r3, lr} 800554d4: e1a00001 mov r0, r1 800554d8: e3a02010 mov r2, #16 ; 0x10 800554dc: e3a01011 mov r1, #17 ; 0x11 800554e0: eb04426e bl 80165ea0 <memset> 800554e4: e1a03000 mov r3, r0 800554e8: e583000c str r0, [r3, #12] 800554ec: e5830000 str r0, [r3] 800554f0: e5830004 str r0, [r3, #4] 800554f4: e8bd8008 pop {r3, pc} GCC assumes memset returns the value of pointer 'waiter' in register r0; causing register/memory corruptions. This patch fixes the return value of the assembly version of memset. It adds a 'mov' instruction and merges an additional load+store into existing load/store instructions. For ease of review, here is a breakdown of the patch into 4 simple steps: Step 1 ====== Perform the following substitutions: ip -> r8, then r0 -> ip, and insert 'mov ip, r0' as the first statement of the function. At this point, we have a memset() implementation returning the proper result, but corrupting r8 on some paths (the ones that were using ip). Step 2 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 1: save r8: - str lr, [sp, #-4]! + stmfd sp!, {r8, lr} and restore r8 on both exit paths: - ldmeqfd sp!, {pc} @ Now <64 bytes to go. + ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go. (...) tst r2, #16 stmneia ip!, {r1, r3, r8, lr} - ldr lr, [sp], #4 + ldmfd sp!, {r8, lr} Step 3 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 0: save r8: - stmfd sp!, {r4-r7, lr} + stmfd sp!, {r4-r8, lr} and restore r8 on both exit paths: bgt 3b - ldmeqfd sp!, {r4-r7, pc} + ldmeqfd sp!, {r4-r8, pc} (...) tst r2, #16 stmneia ip!, {r4-r7} - ldmfd sp!, {r4-r7, lr} + ldmfd sp!, {r4-r8, lr} Step 4 ====== Rewrite register list "r4-r7, r8" as "r4-r8". Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>		12 years ago
..
boot	ARM: 7666/1: decompressor: add -mno-single-pic-base for building the decompressor	12 years ago
common	ARM: GIC: fix GIC cpumask initialization	12 years ago
configs	arm-soc: mvebu platform changes	12 years ago
crypto	ARM: 7626/1: arm/crypto: Make asm SHA-1 and AES code Thumb-2 compatible	12 years ago
include	ARM: 7665/1: Wire up kcmp syscall	12 years ago
kernel	ARM: 7667/1: perf: Fix section mismatch on armpmu_init()	12 years ago
kvm	ARM: KVM: fix compilation after removal of user_alloc from struct kvm_memory_slot	12 years ago
lib	ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) optimizations	12 years ago
mach-at91	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-bcm	Merge remote-tracking branches 'arm-soc/irqchip/gic-vic-move' and 'arm-soc/timer/cleanup' into soc	12 years ago
mach-bcm2835	arm-soc: soc-specific updates	12 years ago
mach-clps711x	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-cns3xxx	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-davinci	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-dove	arm-soc: mvebu platform changes	12 years ago
mach-ebsa110	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-ep93xx	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-exynos	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-footbridge	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-gemini	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-h720x	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-highbank	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-imx	arm-soc: i.MX DT changes	12 years ago
mach-integrator	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-iop13xx	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-iop32x	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-iop33x	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-ixp4xx	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-kirkwood	arm-soc: mvebu platform changes	12 years ago
mach-ks8695	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-l7200/include/mach	…
mach-lpc32xx	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-mmp	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-msm	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-mv78xx0	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-mvebu	arm-soc: mvebu platform changes	12 years ago
mach-mxs	arm-soc: device tree conversions	12 years ago
mach-netx	ARM: 7642/1: netx: bump IRQ offset to 64	12 years ago
mach-nomadik	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-omap1	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-omap2	arm-soc: late OMAP changes	12 years ago
mach-orion5x	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-picoxcell	Merge remote-tracking branches 'arm-soc/irqchip/gic-vic-move' and 'arm-soc/timer/cleanup' into soc	12 years ago
mach-prima2	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-pxa	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-realview	arm-soc: cleanups	12 years ago
mach-rpc	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-s3c24xx	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-s3c64xx	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-s5p64x0	arm-soc: cleanups	12 years ago
mach-s5pc100	Merge remote-tracking branches 'arm-soc/irqchip/gic-vic-move' and 'arm-soc/timer/cleanup' into soc	12 years ago
mach-s5pv210	Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media	12 years ago
mach-sa1100	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-shark	The series cleans up ARCH_HAS_DECOMP_WDOG and arch_decomp_wdog which	12 years ago
mach-shmobile	IOMMU Updates for Linux v3.9	12 years ago
mach-socfpga	Merge branch 'socfpga/hw' into next/soc	12 years ago
mach-spear3xx	Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma	12 years ago
mach-spear6xx	Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma	12 years ago
mach-spear13xx	Revert "ARM: SPEAr13xx: Pass DW DMAC platform data from DT"	12 years ago
mach-sunxi	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-tegra	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-u300	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-ux500	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-versatile	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-vexpress	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
mach-virt	ARM: mach-virt: fixup machine descriptor after removal of sys_timer	12 years ago
mach-vt8500	arm-soc: soc-specific updates	12 years ago
mach-w90x900	arm-soc: cleanups	12 years ago
mach-zynq	arm: zynq: Add missing irqchip.h to common.c	12 years ago
mm	ARM: 7661/1: mm: perform explicit branch predictor maintenance when required	12 years ago
net	ARM: net: bpf_jit: fix emit_swap16() for non ARMv6+.	12 years ago
nwfpe	…
oprofile	…
plat-iop	ARM: use clockevents_config_and_register() where possible	12 years ago
plat-omap	arm-soc: late OMAP changes	12 years ago
plat-orion	arm-soc: cleanups	12 years ago
plat-pxa	ARM: drivers: remove __dev* attributes.	12 years ago
plat-samsung	Merge branch 'timer/cleanup' into late/mvebu2	12 years ago
plat-spear	arm-soc: driver specific changes	12 years ago
plat-versatile	Merge branch 'for-arm-soc/arch-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into kvm-arm/timer	12 years ago
tools	…
vfp	ARM: Fix broken commit `0cc41e4a21` corrupting kernel messages	12 years ago
xen	xen: implement updated XENMEM_add_to_physmap_range ABI	12 years ago
Kconfig	arm-soc: late OMAP changes	12 years ago
Kconfig-nommu	…
Kconfig.debug	arm-soc: soc-specific updates	12 years ago
Makefile	arm-soc: virtualization changes	12 years ago