On Thu, Apr 14, 2016 at 05:20:29PM +0200, Torsten Duwe wrote: > On Thu, Apr 14, 2016 at 11:08:02PM +1000, Michael Ellerman wrote: > > On Thu, 2016-04-14 at 14:57 +0200, Torsten Duwe wrote: > > > > > FTR: then I still have a few ppc64 hunks floating around to support certain consistency > > > models... > > > > OK. I'm not quite sure what you mean but post them and we'll see I guess :) > > It's *roughly* the ppc64 equivalent of Josh Poimboeuf's Mar 25 > | [RFC PATCH v1.9 14/14] livepatch: update task universe when exiting kernel > which only considers x86. > > It's forward ported from an earlier code base; there's some glue missing, > but here it is, for reference. > > Signed-off-by: Torsten Duwe <duwe@xxxxxxx> Hi Torsten, Thanks for sharing. This is quite fortuitous as Miroslav just today mentioned to me that we would need something like this. If you don't mind, I may pull this patch or some variant of it into v2 of the consistency model. > > > diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h > index b034ecd..3e749f4 100644 > --- a/arch/powerpc/include/asm/thread_info.h > +++ b/arch/powerpc/include/asm/thread_info.h > @@ -92,6 +92,7 @@ static inline struct thread_info *current_thread_info(void) > TIF_NEED_RESCHED */ > #define TIF_32BIT 4 /* 32 bit binary */ > #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */ > +#define TIF_KLP_NEED_UPDATE 6 /* kGraft patching in progress */ > #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ > #define TIF_SINGLESTEP 8 /* singlestepping active */ > #define TIF_NOHZ 9 /* in adaptive nohz mode */ > @@ -115,8 +116,10 @@ static inline struct thread_info *current_thread_info(void) > #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) > #define _TIF_32BIT (1<<TIF_32BIT) > #define _TIF_RESTORE_TM (1<<TIF_RESTORE_TM) > +#define _TIF_KLP_NEED_UPDATE (1<<TIF_KLP_NEED_UPDATE) > #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) > #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) > +#define _TIF_NOHZ (1<<TIF_NOHZ) > #define _TIF_SECCOMP (1<<TIF_SECCOMP) > #define _TIF_RESTOREALL (1<<TIF_RESTOREALL) > #define _TIF_NOERROR (1<<TIF_NOERROR) > @@ -124,7 +127,7 @@ static inline struct thread_info *current_thread_info(void) > #define _TIF_UPROBE (1<<TIF_UPROBE) > #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT) > #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE) > -#define _TIF_NOHZ (1<<TIF_NOHZ) > + > #define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ > _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \ > _TIF_NOHZ) > @@ -132,7 +135,8 @@ static inline struct thread_info *current_thread_info(void) > #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ > _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ > _TIF_RESTORE_TM) > -#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR) > + > +#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR|_TIF_KLP_NEED_UPDATE) > > /* Bits in local_flags */ > /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */ > diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S > index 5bbd1bc..17f8a18 100644 > --- a/arch/powerpc/kernel/entry_64.S > +++ b/arch/powerpc/kernel/entry_64.S > @@ -151,8 +151,8 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) > > CURRENT_THREAD_INFO(r11, r1) > ld r10,TI_FLAGS(r11) > - andi. r11,r10,_TIF_SYSCALL_DOTRACE > - bne syscall_dotrace /* does not return */ > + andi. r10,r10,(_TIF_SYSCALL_DOTRACE|_TIF_KLP_NEED_UPDATE) > + bne- syscall_precall /* does not return */ > cmpldi 0,r0,NR_syscalls > bge- syscall_enosys > > @@ -245,6 +245,17 @@ syscall_error: > neg r3,r3 > std r5,_CCR(r1) > b .Lsyscall_error_cont > + > +syscall_precall: > + andi. r10,r10,(_TIF_KLP_NEED_UPDATE) > + beq+ syscall_dotrace > + > + addi r11,r11,TI_FLAGS > +1: ldarx r12,0,r11 > + andc r12,r12,r10 > + stdcx. r12,0,r11 > + bne- 1b > + subi r11,r11,TI_FLAGS > > /* Traced system call support */ > syscall_dotrace: -- Josh -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
