From 247055aa21ffef1c49dd64710d5e94c2aee19b58 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 13 Sep 2010 16:03:21 +0100 Subject: ARM: 6384/1: Remove the domain switching on ARMv6k/v7 CPUs This patch removes the domain switching functionality via the set_fs and __switch_to functions on cores that have a TLS register. Currently, the ioremap and vmalloc areas share the same level 1 page tables and therefore have the same domain (DOMAIN_KERNEL). When the kernel domain is modified from Client to Manager (via the __set_fs or in the __switch_to function), the XN (eXecute Never) bit is overridden and newer CPUs can speculatively prefetch the ioremap'ed memory. Linux performs the kernel domain switching to allow user-specific functions (copy_to/from_user, get/put_user etc.) to access kernel memory. In order for these functions to work with the kernel domain set to Client, the patch modifies the LDRT/STRT and related instructions to the LDR/STR ones. The user pages access rights are also modified for kernel read-only access rather than read/write so that the copy-on-write mechanism still works. CPU_USE_DOMAINS gets disabled only if the hardware has a TLS register (CPU_32v6K is defined) since writing the TLS value to the high vectors page isn't possible. The user addresses passed to the kernel are checked by the access_ok() function so that they do not point to the kernel space. Tested-by: Anton Vorontsov Cc: Tony Lindgren Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/include/asm/traps.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/include/asm/traps.h') diff --git a/arch/arm/include/asm/traps.h b/arch/arm/include/asm/traps.h index 491960bf426..af5d5d1388c 100644 --- a/arch/arm/include/asm/traps.h +++ b/arch/arm/include/asm/traps.h @@ -27,4 +27,6 @@ static inline int in_exception_text(unsigned long ptr) extern void __init early_trap_init(void); extern void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame); +extern void *vectors_page; + #endif -- cgit v1.2.3-70-g09d2 From 61b5cb1c3bff8875d2fd289c7b6ac344f95261fa Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Thu, 7 Oct 2010 20:51:58 +0530 Subject: ARM: place C irq handlers in IRQ_ENTRY for ftrace When FUNCTION_GRAPH_TRACER is enabled, place do_IRQ() and friends in the IRQ_ENTRY section so that the irq-related features of the function graph tracer work. Signed-off-by: Rabin Vincent --- arch/arm/include/asm/system.h | 5 +++++ arch/arm/include/asm/traps.h | 23 +++++++++++++++++++++-- arch/arm/kernel/irq.c | 4 +++- arch/arm/kernel/smp.c | 5 +++-- arch/arm/kernel/vmlinux.lds.S | 1 + 5 files changed, 33 insertions(+), 5 deletions(-) (limited to 'arch/arm/include/asm/traps.h') diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 1120f18a6b1..ec4327a4653 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -63,6 +63,11 @@ #include #define __exception __attribute__((section(".exception.text"))) +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +#define __exception_irq_entry __irq_entry +#else +#define __exception_irq_entry __exception +#endif struct thread_info; struct task_struct; diff --git a/arch/arm/include/asm/traps.h b/arch/arm/include/asm/traps.h index 491960bf426..124475afb00 100644 --- a/arch/arm/include/asm/traps.h +++ b/arch/arm/include/asm/traps.h @@ -15,13 +15,32 @@ struct undef_hook { void register_undef_hook(struct undef_hook *hook); void unregister_undef_hook(struct undef_hook *hook); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static inline int __in_irqentry_text(unsigned long ptr) +{ + extern char __irqentry_text_start[]; + extern char __irqentry_text_end[]; + + return ptr >= (unsigned long)&__irqentry_text_start && + ptr < (unsigned long)&__irqentry_text_end; +} +#else +static inline int __in_irqentry_text(unsigned long ptr) +{ + return 0; +} +#endif + static inline int in_exception_text(unsigned long ptr) { extern char __exception_text_start[]; extern char __exception_text_end[]; + int in; + + in = ptr >= (unsigned long)&__exception_text_start && + ptr < (unsigned long)&__exception_text_end; - return ptr >= (unsigned long)&__exception_text_start && - ptr < (unsigned long)&__exception_text_end; + return in ? : __in_irqentry_text(ptr); } extern void __init early_trap_init(void); diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c index 36ad3be4692..6d616333340 100644 --- a/arch/arm/kernel/irq.c +++ b/arch/arm/kernel/irq.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -105,7 +106,8 @@ unlock: * come via this function. Instead, they should provide their * own 'handler' */ -asmlinkage void __exception asm_do_IRQ(unsigned int irq, struct pt_regs *regs) +asmlinkage void __exception_irq_entry +asm_do_IRQ(unsigned int irq, struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 8c195959025..bbca89872c1 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -457,7 +458,7 @@ static void ipi_timer(void) } #ifdef CONFIG_LOCAL_TIMERS -asmlinkage void __exception do_local_timer(struct pt_regs *regs) +asmlinkage void __exception_irq_entry do_local_timer(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); int cpu = smp_processor_id(); @@ -544,7 +545,7 @@ static void ipi_cpu_stop(unsigned int cpu) * * Bit 0 - Inter-processor function call */ -asmlinkage void __exception do_IPI(struct pt_regs *regs) +asmlinkage void __exception_irq_entry do_IPI(struct pt_regs *regs) { unsigned int cpu = smp_processor_id(); struct ipi_data *ipi = &per_cpu(ipi_data, cpu); diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index cead8893b46..897c1a8f169 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -101,6 +101,7 @@ SECTIONS __exception_text_start = .; *(.exception.text) __exception_text_end = .; + IRQENTRY_TEXT TEXT_TEXT SCHED_TEXT LOCK_TEXT -- cgit v1.2.3-70-g09d2