From: Anshuman Khandual <[email protected]> This patch creates a function flush_tmregs_to_thread which will then be used by subsequent patches in this series. The function checks for self tracing ptrace interface attempts while in the TM context and logs appropriate warning message.
Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Anton Blanchard <[email protected]> Cc: Cyril Bur <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Simon Guo <[email protected]> Cc: Ulrich Weigand <[email protected]> Cc: Michael Neuling <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Kees Cook <[email protected]> Cc: Rashmica Gupta <[email protected]> Cc: Khem Raj <[email protected]> Cc: Jessica Yu <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Miroslav Benes <[email protected]> Cc: Suraj Jitindar Singh <[email protected]> Cc: Chris Smart <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Anshuman Khandual <[email protected]> --- arch/powerpc/include/asm/switch_to.h | 8 ++++++++ arch/powerpc/kernel/process.c | 20 ++++++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 17c8380..0a74ebe 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -75,6 +75,14 @@ static inline void disable_kernel_spe(void) static inline void __giveup_spe(struct task_struct *t) { } #endif +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +extern void flush_tmregs_to_thread(struct task_struct *); +#else +static inline void flush_tmregs_to_thread(struct task_struct *t) +{ +} +#endif + static inline void clear_task_ebb(struct task_struct *t) { #ifdef CONFIG_PPC_BOOK3S_64 diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 0b93893..e9f7f52 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1051,6 +1051,26 @@ static inline void restore_sprs(struct thread_struct *old_thread, #endif } +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +void flush_tmregs_to_thread(struct task_struct *tsk) +{ + /* + * Process self tracing is not yet supported through + * ptrace interface. Ptrace generic code should have + * prevented this from happening in the first place. + * Warn once here with the message, if some how it + * is attempted. + */ + WARN_ONCE(tsk == current, + "Not expecting ptrace on self: TM regs may be incorrect\n"); + + /* + * If task is not current, it should have been flushed + * already to it's thread_struct during __switch_to(). + */ +} +#endif + struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *new) { -- 1.8.3.1
