The patch titled Subject: ptrace/x86: introduce ptrace_register_breakpoint() has been added to the -mm tree. Its filename is ptrace-x86-introduce-ptrace_register_breakpoint.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: ptrace/x86: introduce ptrace_register_breakpoint() No functional changes, preparation. Extract the "register breakpoint" code from ptrace_get_debugreg() into the new/generic helper, ptrace_register_breakpoint(). It will have more users. The patch also adds another simple helper, ptrace_fill_bp_fields(), to factor out the arch_bp_generic_fields() logic in register/modify. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Acked-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jan Kratochvil <jan.kratochvil@xxxxxxxxxx> Cc: Michael Neuling <mikey@xxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Paul Mundt <lethal@xxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Prasad <prasad@xxxxxxxxxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/ptrace.c | 86 +++++++++++++++++++++---------------- 1 file changed, 50 insertions(+), 36 deletions(-) diff -puN arch/x86/kernel/ptrace.c~ptrace-x86-introduce-ptrace_register_breakpoint arch/x86/kernel/ptrace.c --- a/arch/x86/kernel/ptrace.c~ptrace-x86-introduce-ptrace_register_breakpoint +++ a/arch/x86/kernel/ptrace.c @@ -601,22 +601,48 @@ static unsigned long ptrace_get_dr7(stru return dr7; } -static int -ptrace_modify_breakpoint(struct perf_event *bp, int len, int type, - struct task_struct *tsk, int disabled) +static int ptrace_fill_bp_fields(struct perf_event_attr *attr, + int len, int type, bool disabled) +{ + int err, bp_len, bp_type; + + err = arch_bp_generic_fields(len, type, &bp_len, &bp_type); + if (!err) { + attr->bp_len = bp_len; + attr->bp_type = bp_type; + attr->disabled = disabled; + } + + return err; +} + +static struct perf_event * +ptrace_register_breakpoint(struct task_struct *tsk, int len, int type, + unsigned long addr, bool disabled) { - int err; - int gen_len, gen_type; struct perf_event_attr attr; + int err; + + ptrace_breakpoint_init(&attr); + attr.bp_addr = addr; - err = arch_bp_generic_fields(len, type, &gen_len, &gen_type); + err = ptrace_fill_bp_fields(&attr, len, type, disabled); if (err) - return err; + return ERR_PTR(err); - attr = bp->attr; - attr.bp_len = gen_len; - attr.bp_type = gen_type; - attr.disabled = disabled; + return register_user_hw_breakpoint(&attr, ptrace_triggered, + NULL, tsk); +} + +static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type, + int disabled) +{ + struct perf_event_attr attr = bp->attr; + int err; + + err = ptrace_fill_bp_fields(&attr, len, type, disabled); + if (err) + return err; return modify_user_hw_breakpoint(bp, &attr); } @@ -653,7 +679,7 @@ restore: break; } - rc = ptrace_modify_breakpoint(bp, len, type, tsk, disabled); + rc = ptrace_modify_breakpoint(bp, len, type, disabled); if (rc) break; } @@ -693,26 +719,14 @@ static unsigned long ptrace_get_debugreg static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr, unsigned long addr) { - struct perf_event *bp; struct thread_struct *t = &tsk->thread; - struct perf_event_attr attr; + struct perf_event *bp = t->ptrace_bps[nr]; int err = 0; - if (!t->ptrace_bps[nr]) { - ptrace_breakpoint_init(&attr); - /* - * Put stub len and type to register (reserve) an inactive but - * correct bp - */ - attr.bp_addr = addr; - attr.bp_len = HW_BREAKPOINT_LEN_1; - attr.bp_type = HW_BREAKPOINT_W; - attr.disabled = 1; - - bp = register_user_hw_breakpoint(&attr, ptrace_triggered, - NULL, tsk); - + if (!bp) { /* + * Put stub len and type to create an inactive but correct bp. + * * CHECKME: the previous code returned -EIO if the addr wasn't * a valid task virtual addr. The new one will return -EINVAL in * this case. @@ -721,20 +735,20 @@ static int ptrace_set_breakpoint_addr(st * writing for the user. And anyway this is the previous * behaviour. */ - if (IS_ERR(bp)) { + bp = ptrace_register_breakpoint(tsk, + X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE, + addr, true); + if (IS_ERR(bp)) err = PTR_ERR(bp); - goto out; - } - - t->ptrace_bps[nr] = bp; + else + t->ptrace_bps[nr] = bp; } else { - bp = t->ptrace_bps[nr]; + struct perf_event_attr attr = bp->attr; - attr = bp->attr; attr.bp_addr = addr; err = modify_user_hw_breakpoint(bp, &attr); } -out: + return err; } _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are posix_cpu_timer-consolidate-expiry-time-type.patch posix_cpu_timers-consolidate-timer-list-cleanups.patch posix_cpu_timers-consolidate-expired-timers-check.patch posix-timers-correctly-get-dying-task-time-sample-in-posix_cpu_timer_schedule.patch posix_timers-fix-racy-timer-delta-caching-on-task-exit.patch lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch ptrace-x86-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-arm-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-sh-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch ptrace-revert-prepare-to-fix-racy-accesses-on-task-breakpoints.patch ptrace-x86-simplify-the-disable-logic-in-ptrace_write_dr7.patch ptrace-x86-dont-delay-disable-till-second-pass-in-ptrace_write_dr7.patch ptrace-x86-introduce-ptrace_register_breakpoint.patch ptrace-x86-ptrace_write_dr7-should-create-bp-if-disabled.patch ptrace-x86-cleanup-ptrace_set_debugreg.patch ptrace-ptrace_detach-should-do-flush_ptrace_hw_breakpointchild.patch ptrace-x86-flush_ptrace_hw_breakpoint-shoule-clear-the-virtual-debug-registers.patch x86-kill-tif_debug.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html