Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatch updates from Jiri Kosina:
- a per-task consistency model is being added for architectures that
support reliable stack dumping (extending this, currently rather
trivial set, is currently in the works).
This extends the nature of the types of patches that can be applied
by live patching infrastructure. The code stems from the design
proposal made [1] back in November 2014. It's a hybrid of SUSE's
kGraft and RH's kpatch, combining advantages of both: it uses
kGraft's per-task consistency and syscall barrier switching combined
with kpatch's stack trace switching. There are also a number of
fallback options which make it quite flexible.
Most of the heavy lifting done by Josh Poimboeuf with help from
Miroslav Benes and Petr Mladek
[1] https://lkml.kernel.org/r/20141107140458.GA21774@suse.cz
- module load time patch optimization from Zhou Chengming
- a few assorted small fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
livepatch: add missing printk newlines
livepatch: Cancel transition a safe way for immediate patches
livepatch: Reduce the time of finding module symbols
livepatch: make klp_mutex proper part of API
livepatch: allow removal of a disabled patch
livepatch: add /proc/<pid>/patch_state
livepatch: change to a per-task consistency model
livepatch: store function sizes
livepatch: use kstrtobool() in enabled_store()
livepatch: move patching functions into patch.c
livepatch: remove unnecessary object loaded check
livepatch: separate enabled and patched states
livepatch/s390: add TIF_PATCH_PENDING thread flag
livepatch/s390: reorganize TIF thread flag bits
livepatch/powerpc: add TIF_PATCH_PENDING thread flag
livepatch/x86: add TIF_PATCH_PENDING thread flag
livepatch: create temporary klp_update_patch_state() stub
x86/entry: define _TIF_ALLWORK_MASK flags explicitly
stacktrace/x86: add function for detecting reliable stack traces
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index f36e6e2..0b3ee08 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -51,15 +51,14 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
/*
* thread information flags bit numbers
*/
+/* _TIF_WORK bits */
#define TIF_NOTIFY_RESUME 0 /* callback before returning to user */
#define TIF_SIGPENDING 1 /* signal pending */
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_UPROBE 3 /* breakpointed or single-stepping */
#define TIF_GUARDED_STORAGE 4 /* load guarded storage control block */
-#define TIF_SYSCALL_TRACE 8 /* syscall trace active */
-#define TIF_SYSCALL_AUDIT 9 /* syscall auditing active */
-#define TIF_SECCOMP 10 /* secure computing */
-#define TIF_SYSCALL_TRACEPOINT 11 /* syscall tracepoint instrumentation */
+#define TIF_PATCH_PENDING 5 /* pending live patching update */
+
#define TIF_31BIT 16 /* 32bit process */
#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
#define TIF_RESTORE_SIGMASK 18 /* restore signal mask in do_signal() */
@@ -67,16 +66,25 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
#define TIF_BLOCK_STEP 20 /* This task is block stepped */
#define TIF_UPROBE_SINGLESTEP 21 /* This task is uprobe single stepped */
+/* _TIF_TRACE bits */
+#define TIF_SYSCALL_TRACE 24 /* syscall trace active */
+#define TIF_SYSCALL_AUDIT 25 /* syscall auditing active */
+#define TIF_SECCOMP 26 /* secure computing */
+#define TIF_SYSCALL_TRACEPOINT 27 /* syscall tracepoint instrumentation */
+
#define _TIF_NOTIFY_RESUME _BITUL(TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING _BITUL(TIF_SIGPENDING)
#define _TIF_NEED_RESCHED _BITUL(TIF_NEED_RESCHED)
+#define _TIF_UPROBE _BITUL(TIF_UPROBE)
+#define _TIF_GUARDED_STORAGE _BITUL(TIF_GUARDED_STORAGE)
+#define _TIF_PATCH_PENDING _BITUL(TIF_PATCH_PENDING)
+
+#define _TIF_31BIT _BITUL(TIF_31BIT)
+#define _TIF_SINGLE_STEP _BITUL(TIF_SINGLE_STEP)
+
#define _TIF_SYSCALL_TRACE _BITUL(TIF_SYSCALL_TRACE)
#define _TIF_SYSCALL_AUDIT _BITUL(TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP _BITUL(TIF_SECCOMP)
#define _TIF_SYSCALL_TRACEPOINT _BITUL(TIF_SYSCALL_TRACEPOINT)
-#define _TIF_UPROBE _BITUL(TIF_UPROBE)
-#define _TIF_31BIT _BITUL(TIF_31BIT)
-#define _TIF_SINGLE_STEP _BITUL(TIF_SINGLE_STEP)
-#define _TIF_GUARDED_STORAGE _BITUL(TIF_GUARDED_STORAGE)
#endif /* _ASM_THREAD_INFO_H */
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index c6cf338..a5f5d3b 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -47,7 +47,7 @@
STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
_TIF_WORK = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
- _TIF_UPROBE | _TIF_GUARDED_STORAGE)
+ _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING)
_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
_TIF_SYSCALL_TRACEPOINT)
_CIF_WORK = (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \
@@ -334,6 +334,11 @@
jo .Lsysc_guarded_storage
TSTMSK __PT_FLAGS(%r11),_PIF_PER_TRAP
jo .Lsysc_singlestep
+#ifdef CONFIG_LIVEPATCH
+ TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
+ jo .Lsysc_patch_pending # handle live patching just before
+ # signals and possible syscall restart
+#endif
TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
jo .Lsysc_sigpending
TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
@@ -415,6 +420,15 @@
lgr %r2,%r11 # pass pointer to pt_regs
larl %r14,.Lsysc_return
jg gs_load_bc_cb
+#
+# _TIF_PATCH_PENDING is set, call klp_update_patch_state
+#
+#ifdef CONFIG_LIVEPATCH
+.Lsysc_patch_pending:
+ lg %r2,__LC_CURRENT # pass pointer to task struct
+ larl %r14,.Lsysc_return
+ jg klp_update_patch_state
+#endif
#
# _PIF_PER_TRAP is set, call do_per_trap
@@ -667,6 +681,10 @@
jo .Lio_mcck_pending
TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
jo .Lio_reschedule
+#ifdef CONFIG_LIVEPATCH
+ TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
+ jo .Lio_patch_pending
+#endif
TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
jo .Lio_sigpending
TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
@@ -730,6 +748,16 @@
j .Lio_return
#
+# _TIF_PATCH_PENDING is set, call klp_update_patch_state
+#
+#ifdef CONFIG_LIVEPATCH
+.Lio_patch_pending:
+ lg %r2,__LC_CURRENT # pass pointer to task struct
+ larl %r14,.Lio_return
+ jg klp_update_patch_state
+#endif
+
+#
# _TIF_SIGPENDING or is set, call do_signal
#
.Lio_sigpending:
