Hello Linus,
please pull s390 changes for 5.5-rc3.
Thank you,
Vasily
The following changes since commit d1eef1c619749b2a57e514a3fa67d9a516ffa919:
Linux 5.5-rc2 (2019-12-15 15:16:08 -0800)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-5.5-4
for you to fetch changes up to b4adfe55915d8363e244e42386d69567db1719b9:
s390/ftrace: save traced function caller (2019-12-18 23:29:26 +0100)
----------------------------------------------------------------
s390 updates for 5.5-rc3
- Fix unwinding from irq context of interrupted user process.
- Add purgatory build missing symbols check. That helped to uncover and
fix missing symbols when built with kasan support enabled.
- Couple of ftrace fixes. Avoid broken stack trace and fix recursion
loop in function_graph tracer.
----------------------------------------------------------------
Christian Borntraeger (1):
s390/purgatory: do not build purgatory with kcov, kasan and friends
Hans de Goede (1):
s390/purgatory: Make sure we fail the build if purgatory has missing symbols
Sven Schnelle (1):
s390/ftrace: fix endless recursion in function_graph tracer
Vasily Gorbik (2):
s390/unwind: stop gracefully at user mode pt_regs in irq stack
s390/ftrace: save traced function caller
arch/s390/include/asm/timex.h | 4 ++--
arch/s390/kernel/mcount.S | 1 +
arch/s390/kernel/unwind_bc.c | 15 +++++++++++----
arch/s390/purgatory/.gitignore | 1 +
arch/s390/purgatory/Makefile | 19 ++++++++++++++-----
arch/s390/purgatory/string.c | 3 +++
6 files changed, 32 insertions(+), 11 deletions(-)
create mode 100644 arch/s390/purgatory/string.c
diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h
index 6da8885251d6..670f14a228e5 100644
--- a/arch/s390/include/asm/timex.h
+++ b/arch/s390/include/asm/timex.h
@@ -194,9 +194,9 @@ static inline unsigned long long get_tod_clock_monotonic(void)
{
unsigned long long tod;
- preempt_disable();
+ preempt_disable_notrace();
tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1];
- preempt_enable();
+ preempt_enable_notrace();
return tod;
}
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index 9e1660a6b9db..c3597d2e2ae0 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -35,6 +35,7 @@ EXPORT_SYMBOL(_mcount)
ENTRY(ftrace_caller)
.globl ftrace_regs_caller
.set ftrace_regs_caller,ftrace_caller
+ stg %r14,(__SF_GPRS+8*8)(%r15) # save traced function caller
lgr %r1,%r15
#if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT))
aghi %r0,MCOUNT_RETURN_FIXUP
diff --git a/arch/s390/kernel/unwind_bc.c b/arch/s390/kernel/unwind_bc.c
index da2d4d4c5b0e..707fd99f6734 100644
--- a/arch/s390/kernel/unwind_bc.c
+++ b/arch/s390/kernel/unwind_bc.c
@@ -36,10 +36,17 @@ static bool update_stack_info(struct unwind_state *state, unsigned long sp)
return true;
}
-static inline bool is_task_pt_regs(struct unwind_state *state,
- struct pt_regs *regs)
+static inline bool is_final_pt_regs(struct unwind_state *state,
+ struct pt_regs *regs)
{
- return task_pt_regs(state->task) == regs;
+ /* user mode or kernel thread pt_regs at the bottom of task stack */
+ if (task_pt_regs(state->task) == regs)
+ return true;
+
+ /* user mode pt_regs at the bottom of irq stack */
+ return state->stack_info.type == STACK_TYPE_IRQ &&
+ state->stack_info.end - sizeof(struct pt_regs) == (unsigned long)regs &&
+ READ_ONCE_NOCHECK(regs->psw.mask) & PSW_MASK_PSTATE;
}
bool unwind_next_frame(struct unwind_state *state)
@@ -80,7 +87,7 @@ bool unwind_next_frame(struct unwind_state *state)
if (!on_stack(info, sp, sizeof(struct pt_regs)))
goto out_err;
regs = (struct pt_regs *) sp;
- if (is_task_pt_regs(state, regs))
+ if (is_final_pt_regs(state, regs))
goto out_stop;
ip = READ_ONCE_NOCHECK(regs->psw.addr);
sp = READ_ONCE_NOCHECK(regs->gprs[15]);
diff --git a/arch/s390/purgatory/.gitignore b/arch/s390/purgatory/.gitignore
index 04a03433c720..c82157f46b18 100644
--- a/arch/s390/purgatory/.gitignore
+++ b/arch/s390/purgatory/.gitignore
@@ -1,3 +1,4 @@
purgatory
+purgatory.chk
purgatory.lds
purgatory.ro
diff --git a/arch/s390/purgatory/Makefile b/arch/s390/purgatory/Makefile
index bc0d7a0d0394..c57f8c40e992 100644
--- a/arch/s390/purgatory/Makefile
+++ b/arch/s390/purgatory/Makefile
@@ -4,7 +4,7 @@ OBJECT_FILES_NON_STANDARD := y
purgatory-y := head.o purgatory.o string.o sha256.o mem.o
-targets += $(purgatory-y) purgatory.lds purgatory purgatory.ro
+targets += $(purgatory-y) purgatory.lds purgatory purgatory.chk purgatory.ro
PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE
@@ -15,8 +15,10 @@ CFLAGS_sha256.o := -D__DISABLE_EXPORTS
$(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S FORCE
$(call if_changed_rule,as_o_S)
-$(obj)/string.o: $(srctree)/arch/s390/lib/string.c FORCE
- $(call if_changed_rule,cc_o_c)
+KCOV_INSTRUMENT := n
+GCOV_PROFILE := n
+UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
KBUILD_CFLAGS := -fno-strict-aliasing -Wall -Wstrict-prototypes
KBUILD_CFLAGS += -Wno-pointer-sign -Wno-sign-compare
@@ -26,15 +28,22 @@ KBUILD_CFLAGS += $(CLANG_FLAGS)
KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
KBUILD_AFLAGS := $(filter-out -DCC_USING_EXPOLINE,$(KBUILD_AFLAGS))
-LDFLAGS_purgatory := -r --no-undefined -nostdlib -z nodefaultlib -T
+# Since we link purgatory with -r unresolved symbols are not checked, so we
+# also link a purgatory.chk binary without -r to check for unresolved symbols.
+PURGATORY_LDFLAGS := -nostdlib -z nodefaultlib
+LDFLAGS_purgatory := -r $(PURGATORY_LDFLAGS) -T
+LDFLAGS_purgatory.chk := -e purgatory_start $(PURGATORY_LDFLAGS)
$(obj)/purgatory: $(obj)/purgatory.lds $(PURGATORY_OBJS) FORCE
$(call if_changed,ld)
+$(obj)/purgatory.chk: $(obj)/purgatory FORCE
+ $(call if_changed,ld)
+
OBJCOPYFLAGS_purgatory.ro := -O elf64-s390
OBJCOPYFLAGS_purgatory.ro += --remove-section='*debug*'
OBJCOPYFLAGS_purgatory.ro += --remove-section='.comment'
OBJCOPYFLAGS_purgatory.ro += --remove-section='.note.*'
-$(obj)/purgatory.ro: $(obj)/purgatory FORCE
+$(obj)/purgatory.ro: $(obj)/purgatory $(obj)/purgatory.chk FORCE
$(call if_changed,objcopy)
$(obj)/kexec-purgatory.o: $(obj)/kexec-purgatory.S $(obj)/purgatory.ro FORCE
diff --git a/arch/s390/purgatory/string.c b/arch/s390/purgatory/string.c
new file mode 100644
index 000000000000..c98c22a72db7
--- /dev/null
+++ b/arch/s390/purgatory/string.c
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: GPL-2.0
+#define __HAVE_ARCH_MEMCMP /* arch function */
+#include "../lib/string.c"
