diff options
| -rw-r--r-- | arch/x86/kernel/process_32.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/process_64.c | 3 | ||||
| -rw-r--r-- | include/asm-x86/processor_32.h | 2 | ||||
| -rw-r--r-- | include/asm-x86/processor_64.h | 2 | ||||
| -rw-r--r-- | include/asm-x86/thread_info_32.h | 6 | ||||
| -rw-r--r-- | include/asm-x86/thread_info_64.h | 4 |
6 files changed, 19 insertions, 4 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index d9905c9d0fd..d5462f228da 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -602,10 +602,14 @@ static noinline void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, struct tss_struct *tss) { - struct thread_struct *next; + struct thread_struct *prev, *next; + prev = &prev_p->thread; next = &next_p->thread; + if (next->debugctlmsr != prev->debugctlmsr) + wrmsr(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr, 0); + if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { set_debugreg(next->debugreg[0], 0); set_debugreg(next->debugreg[1], 1); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index f7356e5517f..ae5eca17aa3 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -555,6 +555,9 @@ static inline void __switch_to_xtra(struct task_struct *prev_p, prev = &prev_p->thread, next = &next_p->thread; + if (next->debugctlmsr != prev->debugctlmsr) + wrmsrl(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr); + if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { loaddebug(next, 0); loaddebug(next, 1); diff --git a/include/asm-x86/processor_32.h b/include/asm-x86/processor_32.h index 2540bf8d572..3c67eacb316 100644 --- a/include/asm-x86/processor_32.h +++ b/include/asm-x86/processor_32.h @@ -368,6 +368,8 @@ struct thread_struct { unsigned long iopl; /* max allowed port in the bitmap, in bytes: */ unsigned long io_bitmap_max; +/* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */ + unsigned long debugctlmsr; }; #define INIT_THREAD { \ diff --git a/include/asm-x86/processor_64.h b/include/asm-x86/processor_64.h index 20d8935d141..e7bea4fed64 100644 --- a/include/asm-x86/processor_64.h +++ b/include/asm-x86/processor_64.h @@ -238,6 +238,8 @@ struct thread_struct { int ioperm; unsigned long *io_bitmap_ptr; unsigned io_bitmap_max; +/* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */ + unsigned long debugctlmsr; /* cached TLS descriptors. */ u64 tls_array[GDT_ENTRY_TLS_ENTRIES]; } __attribute__((aligned(16))); diff --git a/include/asm-x86/thread_info_32.h b/include/asm-x86/thread_info_32.h index 009ecc6ad38..306fc80800e 100644 --- a/include/asm-x86/thread_info_32.h +++ b/include/asm-x86/thread_info_32.h @@ -139,6 +139,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_FREEZE 19 /* is freezing for suspend */ #define TIF_NOTSC 20 /* TSC is not accessible in userland */ #define TIF_FORCED_TF 21 /* true if TF in eflags artificially */ +#define TIF_DEBUGCTLMSR 22 /* uses thread_struct.debugctlmsr */ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) @@ -155,6 +156,7 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_FREEZE (1<<TIF_FREEZE) #define _TIF_NOTSC (1<<TIF_NOTSC) #define _TIF_FORCED_TF (1<<TIF_FORCED_TF) +#define _TIF_DEBUGCTLMSR (1<<TIF_DEBUGCTLMSR) /* work to do on interrupt/exception return */ #define _TIF_WORK_MASK \ @@ -164,8 +166,8 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP) /* flags to check in __switch_to() */ -#define _TIF_WORK_CTXSW_NEXT (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUG) -#define _TIF_WORK_CTXSW_PREV (_TIF_IO_BITMAP | _TIF_NOTSC) +#define _TIF_WORK_CTXSW_NEXT (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUG | _TIF_DEBUGCTLMSR) +#define _TIF_WORK_CTXSW_PREV (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUGCTLMSR) /* * Thread-synchronous status. diff --git a/include/asm-x86/thread_info_64.h b/include/asm-x86/thread_info_64.h index e0f41b3dece..ee35fd12b54 100644 --- a/include/asm-x86/thread_info_64.h +++ b/include/asm-x86/thread_info_64.h @@ -122,6 +122,7 @@ static inline struct thread_info *stack_thread_info(void) #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ #define TIF_FREEZE 23 /* is freezing for suspend */ #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ +#define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) @@ -140,6 +141,7 @@ static inline struct thread_info *stack_thread_info(void) #define _TIF_IO_BITMAP (1<<TIF_IO_BITMAP) #define _TIF_FREEZE (1<<TIF_FREEZE) #define _TIF_FORCED_TF (1<<TIF_FORCED_TF) +#define _TIF_DEBUGCTLMSR (1<<TIF_DEBUGCTLMSR) /* work to do on interrupt/exception return */ #define _TIF_WORK_MASK \ @@ -151,7 +153,7 @@ static inline struct thread_info *stack_thread_info(void) (_TIF_SIGPENDING|_TIF_SINGLESTEP|_TIF_MCE_NOTIFY|_TIF_HRTICK_RESCHED) /* flags to check in __switch_to() */ -#define _TIF_WORK_CTXSW (_TIF_DEBUG|_TIF_IO_BITMAP) +#define _TIF_WORK_CTXSW (_TIF_DEBUG|_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR) #define PREEMPT_ACTIVE 0x10000000 |