From d0cdef6e87ebc1241d7e407d5e1b14e6bb836ae9 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 25 Sep 2013 23:26:24 +0100 Subject: ARM: 7842/1: MCPM: don't explode if invoked without being initialized first Currently mcpm_cpu_power_down() and mcpm_cpu_suspend() trigger BUG() if mcpm_platform_register() is not called beforehand. This may occur for many reasons such as some incomplete device tree passed to the kernel or the like. Let's be nicer to users and avoid killing the kernel if that happens by logging a warning and returning to the caller. The mcpm_cpu_suspend() user is already set to deal with this situation, and so is cpu_die() invoking mcpm_cpu_die(). The problematic case would have been the B.L switcher's usage of mcpm_cpu_power_down(), however it has to call mcpm_cpu_power_up() first which is already set to catch an error resulting from a missing mcpm_platform_register() call. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/include/asm/mcpm.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/mcpm.h b/arch/arm/include/asm/mcpm.h index 0f7b7620e9a5..fc82a88f5b69 100644 --- a/arch/arm/include/asm/mcpm.h +++ b/arch/arm/include/asm/mcpm.h @@ -76,8 +76,11 @@ int mcpm_cpu_power_up(unsigned int cpu, unsigned int cluster); * * This must be called with interrupts disabled. * - * This does not return. Re-entry in the kernel is expected via - * mcpm_entry_point. + * On success this does not return. Re-entry in the kernel is expected + * via mcpm_entry_point. + * + * This will return if mcpm_platform_register() has not been called + * previously in which case the caller should take appropriate action. */ void mcpm_cpu_power_down(void); @@ -98,8 +101,11 @@ void mcpm_cpu_power_down(void); * * This must be called with interrupts disabled. * - * This does not return. Re-entry in the kernel is expected via - * mcpm_entry_point. + * On success this does not return. Re-entry in the kernel is expected + * via mcpm_entry_point. + * + * This will return if mcpm_platform_register() has not been called + * previously in which case the caller should take appropriate action. */ void mcpm_cpu_suspend(u64 expected_residency); -- cgit v1.2.3 From 262576fffe425ee7768f2686ad5536907d828764 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 26 Sep 2013 15:07:23 +0100 Subject: ARM: 7843/1: drop asm/types.h from generic-y Commit 09096f6 (ARM: 7822/1: add workaround for ambiguous C99 stdint.h types) introduced an ARM specific 'asm/types.h' to work around some ambiguities in the definitions of 32 bit types. Hence, we will not be needing the generic version anymore. Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King --- arch/arm/include/asm/Kbuild | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index d3db39860b9c..59ceae8f3c95 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -31,5 +31,4 @@ generic-y += termbits.h generic-y += termios.h generic-y += timex.h generic-y += trace_clock.h -generic-y += types.h generic-y += unaligned.h -- cgit v1.2.3 From 3f0116c3238a96bc18ad4b4acefe4e7be32fa861 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 10 Oct 2013 10:16:30 +0200 Subject: compiler/gcc4: Add quirk for 'asm goto' miscompilation bug Fengguang Wu, Oleg Nesterov and Peter Zijlstra tracked down a kernel crash to a GCC bug: GCC miscompiles certain 'asm goto' constructs, as outlined here: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 Implement a workaround suggested by Jakub Jelinek. Reported-and-tested-by: Fengguang Wu Reported-by: Oleg Nesterov Reported-by: Peter Zijlstra Suggested-by: Jakub Jelinek Reviewed-by: Richard Henderson Cc: Linus Torvalds Cc: Andrew Morton Cc: Signed-off-by: Ingo Molnar --- arch/arm/include/asm/jump_label.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/jump_label.h b/arch/arm/include/asm/jump_label.h index bfc198c75913..863c892b4aaa 100644 --- a/arch/arm/include/asm/jump_label.h +++ b/arch/arm/include/asm/jump_label.h @@ -16,7 +16,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:\n\t" + asm_volatile_goto("1:\n\t" JUMP_LABEL_NOP "\n\t" ".pushsection __jump_table, \"aw\"\n\t" ".word 1b, %l[l_yes], %c0\n\t" -- cgit v1.2.3 From 3c1532df5c1b54b5f6246cdef94eeb73a39fe43a Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Wed, 9 Oct 2013 15:58:29 +0100 Subject: ARM: 7851/1: check for number of arguments in syscall_get/set_arguments() In ftrace_syscall_enter(), syscall_get_arguments(..., 0, n, ...) if (i == 0) { ...; n--;} memcpy(..., n * sizeof(args[0])); If 'number of arguments(n)' is zero and 'argument index(i)' is also zero in syscall_get_arguments(), none of arguments should be copied by memcpy(). Otherwise 'n--' can be a big positive number and unexpected amount of data will be copied. Tracing system calls which take no argument, say sync(void), may hit this case and eventually make the system corrupted. This patch fixes the issue both in syscall_get_arguments() and syscall_set_arguments(). Cc: Acked-by: Will Deacon Signed-off-by: AKASHI Takahiro Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/include/asm/syscall.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h index f1d96d4e8092..73ddd7239b33 100644 --- a/arch/arm/include/asm/syscall.h +++ b/arch/arm/include/asm/syscall.h @@ -57,6 +57,9 @@ static inline void syscall_get_arguments(struct task_struct *task, unsigned int i, unsigned int n, unsigned long *args) { + if (n == 0) + return; + if (i + n > SYSCALL_MAX_ARGS) { unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i; unsigned int n_bad = n + i - SYSCALL_MAX_ARGS; @@ -81,6 +84,9 @@ static inline void syscall_set_arguments(struct task_struct *task, unsigned int i, unsigned int n, const unsigned long *args) { + if (n == 0) + return; + if (i + n > SYSCALL_MAX_ARGS) { pr_warning("%s called with max args %d, handling only %d\n", __func__, i + n, SYSCALL_MAX_ARGS); -- cgit v1.2.3