* [PATCH v3 2/8] ppc use ftrace_modify_all_code default
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
@ 2015-10-26 17:56 ` Torsten Duwe
2015-10-26 17:57 ` [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (7 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 17:56 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
Convert ppc's arch_ftrace_update_code from its own function copy
to use the generic default functionality (without stop_machine --
our instructions are properly aligned and the replacements atomic ;)
With this we gain error checking and the much-needed function_trace_op
handling.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/kernel/ftrace.c | 16 ++++------------
1 file changed, 4 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 310137f..e419c7b 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -511,20 +511,12 @@ void ftrace_replace_code(int enable)
}
}
+/* Use the default ftrace_modify_all_code, but without
+ * stop_machine().
+ */
void arch_ftrace_update_code(int command)
{
- if (command & FTRACE_UPDATE_CALLS)
- ftrace_replace_code(1);
- else if (command & FTRACE_DISABLE_CALLS)
- ftrace_replace_code(0);
-
- if (command & FTRACE_UPDATE_TRACE_FUNC)
- ftrace_update_ftrace_func(ftrace_trace_function);
-
- if (command & FTRACE_START_FUNC_RET)
- ftrace_enable_ftrace_graph_caller();
- else if (command & FTRACE_STOP_FUNC_RET)
- ftrace_disable_ftrace_graph_caller();
+ ftrace_modify_all_code(command);
}
int __init ftrace_dyn_arch_init(void)
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2)
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
2015-10-26 17:56 ` [PATCH v3 2/8] ppc use ftrace_modify_all_code default Torsten Duwe
@ 2015-10-26 17:57 ` Torsten Duwe
2015-10-27 6:20 ` kbuild test robot
2015-10-26 17:58 ` [PATCH v3 4/8] ppc64 ftrace_with_regs: spare early boot and low level Torsten Duwe
` (6 subsequent siblings)
8 siblings, 1 reply; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 17:57 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
* Makefile:
- globally use -mprofile-kernel in case it's configured.
* arch/powerpc/Kconfig / kernel/trace/Kconfig:
- declare that ppc64 HAVE_MPROFILE_KERNEL and
HAVE_DYNAMIC_FTRACE_WITH_REGS, and use it.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/Kconfig | 2 ++
arch/powerpc/Makefile | 7 +++++++
kernel/trace/Kconfig | 5 +++++
3 files changed, 14 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9a7057e..0e6011c 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -97,8 +97,10 @@ config PPC
select OF_RESERVED_MEM
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
+ select HAVE_DYNAMIC_FTRACE_WITH_REGS
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_MPROFILE_KERNEL
select SYSCTL_EXCEPTION_TRACE
select ARCH_WANT_OPTIONAL_GPIOLIB
select VIRT_TO_BUS if !PPC64
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index b9b4af2..25d0034 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -133,6 +133,13 @@ else
CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64
endif
+ifeq ($(CONFIG_PPC64),y)
+ifdef CONFIG_HAVE_MPROFILE_KERNEL
+CC_FLAGS_FTRACE := -pg $(call cc-option,-mprofile-kernel)
+KBUILD_CPPFLAGS += -DCC_USING_MPROFILE_KERNEL
+endif
+endif
+
CFLAGS-$(CONFIG_CELL_CPU) += $(call cc-option,-mcpu=cell)
CFLAGS-$(CONFIG_POWER4_CPU) += $(call cc-option,-mcpu=power4)
CFLAGS-$(CONFIG_POWER5_CPU) += $(call cc-option,-mcpu=power5)
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1153c43..dbcb635 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -52,6 +52,11 @@ config HAVE_FENTRY
help
Arch supports the gcc options -pg with -mfentry
+config HAVE_MPROFILE_KERNEL
+ bool
+ help
+ Arch supports the gcc options -pg with -mprofile-kernel
+
config HAVE_C_RECORDMCOUNT
bool
help
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: Re: [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2)
2015-10-26 17:57 ` [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
@ 2015-10-27 6:20 ` kbuild test robot
0 siblings, 0 replies; 11+ messages in thread
From: kbuild test robot @ 2015-10-27 6:20 UTC (permalink / raw)
To: Torsten Duwe
Cc: kbuild-all, Steven Rostedt, Michael Ellerman, Jiri Kosina,
linuxppc-dev, linux-kernel, live-patching
[-- Attachment #1: Type: text/plain, Size: 5285 bytes --]
Hi Torsten,
[auto build test ERROR on powerpc/next -- if it's inappropriate base, please suggest rules for selecting the more suitable base]
url: https://github.com/0day-ci/linux/commits/Torsten-Duwe/Re-PATCH-v3-0-8-ftrace-with-regs-live-patching-for-ppc64-LE-ABI-v2/20151027-020058
config: powerpc-ppc6xx_defconfig (attached as .config)
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
All errors (new ones prefixed by >>):
kernel/built-in.o: In function `ftrace_get_addr_curr':
>> kernel/trace/ftrace.c:2286: undefined reference to `ftrace_regs_caller'
>> kernel/trace/ftrace.c:2286: undefined reference to `ftrace_regs_caller'
kernel/built-in.o: In function `ftrace_get_addr_new':
kernel/trace/ftrace.c:2254: undefined reference to `ftrace_regs_caller'
kernel/trace/ftrace.c:2254: undefined reference to `ftrace_regs_caller'
kernel/built-in.o: In function `__ftrace_replace_code':
>> kernel/trace/ftrace.c:2316: undefined reference to `ftrace_modify_call'
kernel/built-in.o: In function `ftrace_get_addr_curr':
>> kernel/trace/ftrace.c:2286: undefined reference to `ftrace_regs_caller'
>> kernel/trace/ftrace.c:2286: undefined reference to `ftrace_regs_caller'
kernel/built-in.o: In function `ftrace_get_addr_new':
kernel/trace/ftrace.c:2254: undefined reference to `ftrace_regs_caller'
kernel/trace/ftrace.c:2254: undefined reference to `ftrace_regs_caller'
kernel/built-in.o: In function `ftrace_get_addr_curr':
>> kernel/trace/ftrace.c:2286: undefined reference to `ftrace_regs_caller'
kernel/built-in.o:kernel/trace/ftrace.c:2286: more undefined references to `ftrace_regs_caller' follow
vim +2286 kernel/trace/ftrace.c
79922b80 Steven Rostedt (Red Hat 2014-05-06 2280) return (unsigned long)FTRACE_ADDR;
79922b80 Steven Rostedt (Red Hat 2014-05-06 2281) }
79922b80 Steven Rostedt (Red Hat 2014-05-06 2282) return ops->trampoline;
79922b80 Steven Rostedt (Red Hat 2014-05-06 2283) }
79922b80 Steven Rostedt (Red Hat 2014-05-06 2284)
7413af1f Steven Rostedt (Red Hat 2014-05-06 2285) if (rec->flags & FTRACE_FL_REGS_EN)
7413af1f Steven Rostedt (Red Hat 2014-05-06 @2286) return (unsigned long)FTRACE_REGS_ADDR;
7413af1f Steven Rostedt (Red Hat 2014-05-06 2287) else
7413af1f Steven Rostedt (Red Hat 2014-05-06 2288) return (unsigned long)FTRACE_ADDR;
7413af1f Steven Rostedt (Red Hat 2014-05-06 2289) }
7413af1f Steven Rostedt (Red Hat 2014-05-06 2290)
c88fd863 Steven Rostedt 2011-08-16 2291 static int
c88fd863 Steven Rostedt 2011-08-16 2292 __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
c88fd863 Steven Rostedt 2011-08-16 2293 {
08f6fba5 Steven Rostedt 2012-04-30 2294 unsigned long ftrace_old_addr;
c88fd863 Steven Rostedt 2011-08-16 2295 unsigned long ftrace_addr;
c88fd863 Steven Rostedt 2011-08-16 2296 int ret;
c88fd863 Steven Rostedt 2011-08-16 2297
7c0868e0 Steven Rostedt (Red Hat 2014-05-08 2298) ftrace_addr = ftrace_get_addr_new(rec);
c88fd863 Steven Rostedt 2011-08-16 2299
7c0868e0 Steven Rostedt (Red Hat 2014-05-08 2300) /* This needs to be done before we call ftrace_update_record */
7c0868e0 Steven Rostedt (Red Hat 2014-05-08 2301) ftrace_old_addr = ftrace_get_addr_curr(rec);
7c0868e0 Steven Rostedt (Red Hat 2014-05-08 2302)
7c0868e0 Steven Rostedt (Red Hat 2014-05-08 2303) ret = ftrace_update_record(rec, enable);
08f6fba5 Steven Rostedt 2012-04-30 2304
c88fd863 Steven Rostedt 2011-08-16 2305 switch (ret) {
c88fd863 Steven Rostedt 2011-08-16 2306 case FTRACE_UPDATE_IGNORE:
c88fd863 Steven Rostedt 2011-08-16 2307 return 0;
c88fd863 Steven Rostedt 2011-08-16 2308
c88fd863 Steven Rostedt 2011-08-16 2309 case FTRACE_UPDATE_MAKE_CALL:
c88fd863 Steven Rostedt 2011-08-16 2310 return ftrace_make_call(rec, ftrace_addr);
c88fd863 Steven Rostedt 2011-08-16 2311
c88fd863 Steven Rostedt 2011-08-16 2312 case FTRACE_UPDATE_MAKE_NOP:
39b5552c Steven Rostedt (Red Hat 2014-08-17 2313) return ftrace_make_nop(NULL, rec, ftrace_old_addr);
08f6fba5 Steven Rostedt 2012-04-30 2314
08f6fba5 Steven Rostedt 2012-04-30 2315 case FTRACE_UPDATE_MODIFY_CALL:
08f6fba5 Steven Rostedt 2012-04-30 @2316 return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
5072c59f Steven Rostedt 2008-05-12 2317 }
5072c59f Steven Rostedt 2008-05-12 2318
c88fd863 Steven Rostedt 2011-08-16 2319 return -1; /* unknow ftrace bug */
:::::: The code at line 2286 was first introduced by commit
:::::: 7413af1fb70e7efa6dbc7f27663e7a5126b3aa33 ftrace: Make get_ftrace_addr() and get_ftrace_addr_old() global
:::::: TO: Steven Rostedt (Red Hat) <rostedt@goodmis.org>
:::::: CC: Steven Rostedt <rostedt@goodmis.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 27240 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH v3 4/8] ppc64 ftrace_with_regs: spare early boot and low level
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
2015-10-26 17:56 ` [PATCH v3 2/8] ppc use ftrace_modify_all_code default Torsten Duwe
2015-10-26 17:57 ` [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
@ 2015-10-26 17:58 ` Torsten Duwe
2015-10-26 17:59 ` [PATCH v3 5/8] ppc64 ftrace: disable profiling for some functions Torsten Duwe
` (5 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 17:58 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
Using -mprofile-kernel on early boot code not only confuses the
checker but is also useless, as the infrastructure is not yet in
place. Proceed like with -pg (remove it from CFLAGS), equally with
time.o and ftrace itself.
* arch/powerpc/kernel/Makefile:
- remove -mprofile-kernel from low level and boot code objects'
CFLAGS for FUNCTION_TRACER configurations.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/kernel/Makefile | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index ba33693..0f417d5 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -16,14 +16,14 @@ endif
ifdef CONFIG_FUNCTION_TRACER
# Do not trace early boot code
-CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog
-CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog
-CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog
-CFLAGS_REMOVE_prom.o = -pg -mno-sched-epilog
+CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog -mprofile-kernel
+CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog -mprofile-kernel
+CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog -mprofile-kernel
+CFLAGS_REMOVE_prom.o = -pg -mno-sched-epilog -mprofile-kernel
# do not trace tracer code
-CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog
+CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog -mprofile-kernel
# timers used by tracing
-CFLAGS_REMOVE_time.o = -pg -mno-sched-epilog
+CFLAGS_REMOVE_time.o = -pg -mno-sched-epilog -mprofile-kernel
endif
obj-y := cputable.o ptrace.o syscalls.o \
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 5/8] ppc64 ftrace: disable profiling for some functions
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (2 preceding siblings ...)
2015-10-26 17:58 ` [PATCH v3 4/8] ppc64 ftrace_with_regs: spare early boot and low level Torsten Duwe
@ 2015-10-26 17:59 ` Torsten Duwe
2015-10-26 18:01 ` [PATCH v3 6/8] ppc64 ftrace: disable profiling for some files Torsten Duwe
` (4 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 17:59 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
At least POWER7/8 have MMUs that don't completely autoload;
a normal, recoverable memory fault might pass through these functions.
If a dynamic tracer function causes such a fault, any of these functions
being traced with -mprofile-kernel may cause an endless recursion.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/kernel/process.c | 2 +-
arch/powerpc/mm/fault.c | 2 +-
arch/powerpc/mm/hash_utils_64.c | 18 +++++++++---------
arch/powerpc/mm/hugetlbpage-hash64.c | 2 +-
arch/powerpc/mm/hugetlbpage.c | 4 ++--
arch/powerpc/mm/mem.c | 2 +-
arch/powerpc/mm/pgtable_64.c | 2 +-
arch/powerpc/mm/slb.c | 6 +++---
arch/powerpc/mm/slice.c | 8 ++++----
9 files changed, 23 insertions(+), 23 deletions(-)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 75b6676..c2900b9 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -715,7 +715,7 @@ static inline void __switch_to_tm(struct task_struct *prev)
* don't know which of the checkpointed state and the transactional
* state to use.
*/
-void restore_tm_state(struct pt_regs *regs)
+notrace void restore_tm_state(struct pt_regs *regs)
{
unsigned long msr_diff;
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index a67c6d7..125be37 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -205,7 +205,7 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
* The return value is 0 if the fault was handled, or the signal
* number if this is a kernel fault that can't be handled here.
*/
-int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
+notrace int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
unsigned long error_code)
{
enum ctx_state prev_state = exception_enter();
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index aee7017..90e89e7 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -849,7 +849,7 @@ void early_init_mmu_secondary(void)
/*
* Called by asm hashtable.S for doing lazy icache flush
*/
-unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
+notrace unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
{
struct page *page;
@@ -870,7 +870,7 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
}
#ifdef CONFIG_PPC_MM_SLICES
-static unsigned int get_paca_psize(unsigned long addr)
+static notrace unsigned int get_paca_psize(unsigned long addr)
{
u64 lpsizes;
unsigned char *hpsizes;
@@ -899,7 +899,7 @@ unsigned int get_paca_psize(unsigned long addr)
* For now this makes the whole process use 4k pages.
*/
#ifdef CONFIG_PPC_64K_PAGES
-void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
+notrace void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
{
if (get_slice_psize(mm, addr) == MMU_PAGE_4K)
return;
@@ -920,7 +920,7 @@ void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
* Result is 0: full permissions, _PAGE_RW: read-only,
* _PAGE_USER or _PAGE_USER|_PAGE_RW: no access.
*/
-static int subpage_protection(struct mm_struct *mm, unsigned long ea)
+static notrace int subpage_protection(struct mm_struct *mm, unsigned long ea)
{
struct subpage_prot_table *spt = &mm->context.spt;
u32 spp = 0;
@@ -968,7 +968,7 @@ void hash_failure_debug(unsigned long ea, unsigned long access,
trap, vsid, ssize, psize, lpsize, pte);
}
-static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
+static notrace void check_paca_psize(unsigned long ea, struct mm_struct *mm,
int psize, bool user_region)
{
if (user_region) {
@@ -990,7 +990,7 @@ static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
* -1 - critical hash insertion error
* -2 - access not permitted by subpage protection mechanism
*/
-int hash_page_mm(struct mm_struct *mm, unsigned long ea,
+notrace int hash_page_mm(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap,
unsigned long flags)
{
@@ -1186,7 +1186,7 @@ bail:
}
EXPORT_SYMBOL_GPL(hash_page_mm);
-int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
+notrace int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
unsigned long dsisr)
{
unsigned long flags = 0;
@@ -1288,7 +1288,7 @@ out_exit:
/* WARNING: This is called from hash_low_64.S, if you change this prototype,
* do not forget to update the assembly call site !
*/
-void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize,
+notrace void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize,
unsigned long flags)
{
unsigned long hash, index, shift, hidx, slot;
@@ -1436,7 +1436,7 @@ void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
exception_exit(prev_state);
}
-long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
+notrace long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
unsigned long pa, unsigned long rflags,
unsigned long vflags, int psize, int ssize)
{
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index d94b1af..50b8c6f 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -18,7 +18,7 @@ extern long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
unsigned long pa, unsigned long rlags,
unsigned long vflags, int psize, int ssize);
-int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
+notrace int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
int ssize, unsigned int shift, unsigned int mmu_psize)
{
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 06c1452..bc2f459 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -922,7 +922,7 @@ static int __init hugetlbpage_init(void)
#endif
arch_initcall(hugetlbpage_init);
-void flush_dcache_icache_hugepage(struct page *page)
+notrace void flush_dcache_icache_hugepage(struct page *page)
{
int i;
void *start;
@@ -955,7 +955,7 @@ void flush_dcache_icache_hugepage(struct page *page)
* when we have MSR[EE] = 0 but the paca->soft_enabled = 1
*/
-pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
+notrace pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
unsigned *shift)
{
pgd_t pgd, *pgdp;
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 22d94c3..f690e8a 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -406,7 +406,7 @@ void flush_dcache_page(struct page *page)
}
EXPORT_SYMBOL(flush_dcache_page);
-void flush_dcache_icache_page(struct page *page)
+notrace void flush_dcache_icache_page(struct page *page)
{
#ifdef CONFIG_HUGETLB_PAGE
if (PageCompound(page)) {
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index e92cb21..c74050b 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -442,7 +442,7 @@ static void page_table_free_rcu(void *table)
}
}
-void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift)
+notrace void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift)
{
unsigned long pgf = (unsigned long)table;
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 8a32a2b..5b05754 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -91,7 +91,7 @@ static inline void create_shadowed_slbe(unsigned long ea, int ssize,
: "memory" );
}
-static void __slb_flush_and_rebolt(void)
+static notrace void __slb_flush_and_rebolt(void)
{
/* If you change this make sure you change SLB_NUM_BOLTED
* and PR KVM appropriately too. */
@@ -131,7 +131,7 @@ static void __slb_flush_and_rebolt(void)
: "memory");
}
-void slb_flush_and_rebolt(void)
+notrace void slb_flush_and_rebolt(void)
{
WARN_ON(!irqs_disabled());
@@ -146,7 +146,7 @@ void slb_flush_and_rebolt(void)
get_paca()->slb_cache_ptr = 0;
}
-void slb_vmalloc_update(void)
+notrace void slb_vmalloc_update(void)
{
unsigned long vflags;
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 0f432a7..f92f0f0 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -76,8 +76,8 @@ static void slice_print_mask(const char *label, struct slice_mask mask) {}
#endif
-static struct slice_mask slice_range_to_mask(unsigned long start,
- unsigned long len)
+static notrace struct slice_mask slice_range_to_mask(unsigned long start,
+ unsigned long len)
{
unsigned long end = start + len - 1;
struct slice_mask ret = { 0, 0 };
@@ -564,7 +564,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
current->mm->context.user_psize, 1);
}
-unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
+notrace unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
{
unsigned char *hpsizes;
int index, mask_index;
@@ -645,7 +645,7 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
spin_unlock_irqrestore(&slice_convert_lock, flags);
}
-void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
+notrace void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
unsigned long len, unsigned int psize)
{
struct slice_mask mask = slice_range_to_mask(start, len);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 6/8] ppc64 ftrace: disable profiling for some files
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (3 preceding siblings ...)
2015-10-26 17:59 ` [PATCH v3 5/8] ppc64 ftrace: disable profiling for some functions Torsten Duwe
@ 2015-10-26 18:01 ` Torsten Duwe
2015-10-26 18:02 ` [PATCH v3 7/8] Implement kernel live patching for ppc64le (ABIv2) Torsten Duwe
` (3 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 18:01 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
This adds -mprofile-kernel to the cc flags to be stripped from the command
line for code-patching.o and feature-fixups.o, in addition to "-pg"
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/lib/Makefile | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index a47e142..98e22b2 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -6,8 +6,8 @@ subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
-CFLAGS_REMOVE_code-patching.o = -pg
-CFLAGS_REMOVE_feature-fixups.o = -pg
+CFLAGS_REMOVE_code-patching.o = -pg -mprofile-kernel
+CFLAGS_REMOVE_feature-fixups.o = -pg -mprofile-kernel
obj-y += string.o alloc.o crtsavres.o ppc_ksyms.o code-patching.o \
feature-fixups.o
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 7/8] Implement kernel live patching for ppc64le (ABIv2)
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (4 preceding siblings ...)
2015-10-26 18:01 ` [PATCH v3 6/8] ppc64 ftrace: disable profiling for some files Torsten Duwe
@ 2015-10-26 18:02 ` Torsten Duwe
2015-10-26 18:02 ` [PATCH v3 8/8] Enable LIVEPATCH to be configured on ppc64le and add livepatch.o if it is selected Torsten Duwe
` (2 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 18:02 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
* create the appropriate files+functions
arch/powerpc/include/asm/livepatch.h
klp_check_compiler_support,
klp_arch_set_pc
arch/powerpc/kernel/livepatch.c with a stub for
klp_write_module_reloc
This is architecture-independent work in progress.
* introduce a fixup in arch/powerpc/kernel/entry_64.S
for local calls that are becoming global due to live patching.
And of course do the main KLP thing: return to a maybe different
address, possibly altered by the live patching ftrace op.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/include/asm/livepatch.h | 27 ++++++++++++++++++++
arch/powerpc/kernel/entry_64.S | 48 +++++++++++++++++++++++++++++++++---
arch/powerpc/kernel/livepatch.c | 20 +++++++++++++++
3 files changed, 91 insertions(+), 4 deletions(-)
create mode 100644 arch/powerpc/include/asm/livepatch.h
create mode 100644 arch/powerpc/kernel/livepatch.c
diff --git a/arch/powerpc/include/asm/livepatch.h b/arch/powerpc/include/asm/livepatch.h
new file mode 100644
index 0000000..334eb55
--- /dev/null
+++ b/arch/powerpc/include/asm/livepatch.h
@@ -0,0 +1,27 @@
+#ifndef _ASM_POWERPC64_LIVEPATCH_H
+#define _ASM_POWERPC64_LIVEPATCH_H
+
+#include <linux/module.h>
+#include <linux/ftrace.h>
+
+#ifdef CONFIG_LIVEPATCH
+static inline int klp_check_compiler_support(void)
+{
+#if !defined(_CALL_ELF) || _CALL_ELF != 2
+ return 1;
+#endif
+ return 0;
+}
+
+extern int klp_write_module_reloc(struct module *mod, unsigned long type,
+ unsigned long loc, unsigned long value);
+
+static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->nip = ip;
+}
+#else
+#error Live patching support is disabled; check CONFIG_LIVEPATCH
+#endif
+
+#endif /* _ASM_POWERPC64_LIVEPATCH_H */
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index b0dfbfe..2681601 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -1264,6 +1264,9 @@ _GLOBAL(ftrace_caller)
mflr r3
std r3, _NIP(r1)
std r3, 16(r1)
+#ifdef CONFIG_LIVEPATCH
+ mr r14,r3 // remember "old" NIP
+#endif
subi r3, r3, MCOUNT_INSN_SIZE
mfmsr r4
std r4, _MSR(r1)
@@ -1280,7 +1283,10 @@ ftrace_call:
nop
ld r3, _NIP(r1)
- mtlr r3
+ mtctr r3 // prepare to jump there
+#ifdef CONFIG_LIVEPATCH
+ cmpd r14,r3 // has NIP been altered?
+#endif
REST_8GPRS(0,r1)
REST_8GPRS(8,r1)
@@ -1293,6 +1299,24 @@ ftrace_call:
mtlr r12
mr r2,r0 // restore callee's TOC
+#ifdef CONFIG_LIVEPATCH
+ beq+ 4f // likely(old_NIP == new_NIP)
+
+ // For a local call, restore this TOC after calling the patch function.
+ // For a global call, it does not matter what we restore here,
+ // since the global caller does its own restore right afterwards,
+ // anyway.
+ // Just insert a KLP_return_helper frame in any case,
+ // so a patch function can always count on the changed stack offsets.
+ stdu r1,-32(r1) // open new mini stack frame
+ std r0,24(r1) // save TOC now, unconditionally.
+ LOAD_REG_IMMEDIATE(r12,KLP_return_helper)
+ std r12,LRSAVE(r1)
+ mtlr r12
+ bctr
+4:
+#endif
+
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
stdu r1, -112(r1)
.globl ftrace_graph_call
@@ -1302,15 +1326,31 @@ _GLOBAL(ftrace_graph_stub)
addi r1, r1, 112
#endif
- mflr r0 // move this LR to CTR
- mtctr r0
-
ld r0,LRSAVE(r1) // restore callee's lr at _mcount site
mtlr r0
bctr // jump after _mcount site
#endif /* CC_USING_MPROFILE_KERNEL */
_GLOBAL(ftrace_stub)
blr
+
+#ifdef CONFIG_LIVEPATCH
+/* Helper function for local calls that are becoming global
+ due to live patching.
+ We can't simply patch the NOP after the original call,
+ because, depending on the consistency model, some kernel
+ threads may still have called the original, local function
+ *without* saving their TOC in the respective stack frame slot,
+ so the decision is made per-thread during function return by
+ maybe inserting a KLP_return_helper frame or not.
+*/
+KLP_return_helper:
+ ld r2,24(r1) // restore TOC (saved by ftrace_caller)
+ addi r1, r1, 32 // destroy mini stack frame
+ ld r0,LRSAVE(r1) // get the real return address
+ mtlr r0
+ blr
+#endif
+
#else
_GLOBAL_TOC(_mcount)
/* Taken from output of objdump from lib64/glibc */
diff --git a/arch/powerpc/kernel/livepatch.c b/arch/powerpc/kernel/livepatch.c
new file mode 100644
index 0000000..9dace38
--- /dev/null
+++ b/arch/powerpc/kernel/livepatch.c
@@ -0,0 +1,20 @@
+#include <linux/module.h>
+#include <asm/livepatch.h>
+
+/**
+ * klp_write_module_reloc() - write a relocation in a module
+ * @mod: module in which the section to be modified is found
+ * @type: ELF relocation type (see asm/elf.h)
+ * @loc: address that the relocation should be written to
+ * @value: relocation value (sym address + addend)
+ *
+ * This function writes a relocation to the specified location for
+ * a particular module.
+ */
+int klp_write_module_reloc(struct module *mod, unsigned long type,
+ unsigned long loc, unsigned long value)
+{
+ /* This requires infrastructure changes; we need the loadinfos. */
+ pr_err("lpc_write_module_reloc not yet supported\n");
+ return -ENOSYS;
+}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 8/8] Enable LIVEPATCH to be configured on ppc64le and add livepatch.o if it is selected.
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (5 preceding siblings ...)
2015-10-26 18:02 ` [PATCH v3 7/8] Implement kernel live patching for ppc64le (ABIv2) Torsten Duwe
@ 2015-10-26 18:02 ` Torsten Duwe
2015-10-26 18:03 ` [PATCH v3 3/8] ppc64 ftrace_with_regs configuration variables Torsten Duwe
2015-10-26 18:04 ` [PATCH v3 1/8] ppc64le FTRACE_WITH_REGS implementation Torsten Duwe
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 18:02 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/Kconfig | 5 +++++
arch/powerpc/kernel/Makefile | 1 +
2 files changed, 6 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 0e6011c..341ebe9 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -163,6 +163,9 @@ config PPC
select ARCH_HAS_DMA_SET_COHERENT_MASK
select HAVE_ARCH_SECCOMP_FILTER
+config HAVE_LIVEPATCH
+ def_bool PPC64 && CPU_LITTLE_ENDIAN
+
config GENERIC_CSUM
def_bool CPU_LITTLE_ENDIAN
@@ -1095,3 +1098,5 @@ config PPC_LIB_RHEAP
bool
source "arch/powerpc/kvm/Kconfig"
+
+source "kernel/livepatch/Kconfig"
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 0f417d5..f9a2925 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -119,6 +119,7 @@ obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_TRACING) += trace_clock.o
+obj-$(CONFIG_LIVEPATCH) += livepatch.o
ifneq ($(CONFIG_PPC_INDIRECT_PIO),y)
obj-y += iomap.o
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 3/8] ppc64 ftrace_with_regs configuration variables
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (6 preceding siblings ...)
2015-10-26 18:02 ` [PATCH v3 8/8] Enable LIVEPATCH to be configured on ppc64le and add livepatch.o if it is selected Torsten Duwe
@ 2015-10-26 18:03 ` Torsten Duwe
2015-10-26 18:04 ` [PATCH v3 1/8] ppc64le FTRACE_WITH_REGS implementation Torsten Duwe
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 18:03 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
* Makefile:
- globally use -mprofile-kernel in case it's configured.
* arch/powerpc/Kconfig / kernel/trace/Kconfig:
- declare that ppc64 HAVE_MPROFILE_KERNEL and
HAVE_DYNAMIC_FTRACE_WITH_REGS, and use it.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/Kconfig | 2 ++
arch/powerpc/Makefile | 7 +++++++
kernel/trace/Kconfig | 5 +++++
3 files changed, 14 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9a7057e..0e6011c 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -97,8 +97,10 @@ config PPC
select OF_RESERVED_MEM
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
+ select HAVE_DYNAMIC_FTRACE_WITH_REGS
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_MPROFILE_KERNEL
select SYSCTL_EXCEPTION_TRACE
select ARCH_WANT_OPTIONAL_GPIOLIB
select VIRT_TO_BUS if !PPC64
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index b9b4af2..25d0034 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -133,6 +133,13 @@ else
CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64
endif
+ifeq ($(CONFIG_PPC64),y)
+ifdef CONFIG_HAVE_MPROFILE_KERNEL
+CC_FLAGS_FTRACE := -pg $(call cc-option,-mprofile-kernel)
+KBUILD_CPPFLAGS += -DCC_USING_MPROFILE_KERNEL
+endif
+endif
+
CFLAGS-$(CONFIG_CELL_CPU) += $(call cc-option,-mcpu=cell)
CFLAGS-$(CONFIG_POWER4_CPU) += $(call cc-option,-mcpu=power4)
CFLAGS-$(CONFIG_POWER5_CPU) += $(call cc-option,-mcpu=power5)
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1153c43..dbcb635 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -52,6 +52,11 @@ config HAVE_FENTRY
help
Arch supports the gcc options -pg with -mfentry
+config HAVE_MPROFILE_KERNEL
+ bool
+ help
+ Arch supports the gcc options -pg with -mprofile-kernel
+
config HAVE_C_RECORDMCOUNT
bool
help
--
1.8.5.6
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH v3 1/8] ppc64le FTRACE_WITH_REGS implementation
2015-10-26 17:49 [PATCH v3 0/8] ftrace with regs + live patching for ppc64 LE (ABI v2) Torsten Duwe
` (7 preceding siblings ...)
2015-10-26 18:03 ` [PATCH v3 3/8] ppc64 ftrace_with_regs configuration variables Torsten Duwe
@ 2015-10-26 18:04 ` Torsten Duwe
8 siblings, 0 replies; 11+ messages in thread
From: Torsten Duwe @ 2015-10-26 18:04 UTC (permalink / raw)
To: Steven Rostedt, Michael Ellerman
Cc: Jiri Kosina, linuxppc-dev, linux-kernel, live-patching
Implement FTRACE_WITH_REGS for powerpc64, on ELF ABI v2.
Initial work started by Vojtech Pavlik, used with permission.
* arch/powerpc/kernel/entry_64.S:
- enhance _mcount with a stub to support call sites
generated by -mprofile-kernel. This is backward-compatible.
- Implement an effective ftrace_caller that works from
within the kernel binary as well as from modules.
* arch/powerpc/kernel/ftrace.c:
- be prepared to deal with ppc64 ELF ABI v2, especially
calls to _mcount that result from gcc -mprofile-kernel
- a little more error verbosity
* arch/powerpc/kernel/module_64.c:
- do not save the TOC pointer on the trampoline when the
destination is ftrace_caller. This trampoline jump happens from
a function prologue before a new stack frame is set up, so bad
things may happen otherwise...
- relax is_module_trampoline() to recognise the modified
trampoline.
Signed-off-by: Torsten Duwe <duwe@suse.de>
---
arch/powerpc/include/asm/ftrace.h | 5 ++
arch/powerpc/kernel/entry_64.S | 113 +++++++++++++++++++++++++++++++++++++-
arch/powerpc/kernel/ftrace.c | 72 +++++++++++++++++++++---
arch/powerpc/kernel/module_64.c | 39 ++++++++++++-
4 files changed, 217 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h
index ef89b14..6eb9fbc 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -46,6 +46,8 @@
extern void _mcount(void);
#ifdef CONFIG_DYNAMIC_FTRACE
+# define FTRACE_ADDR ((unsigned long)ftrace_caller)
+# define FTRACE_REGS_ADDR FTRACE_ADDR
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
/* reloction of mcount call site is the same as the address */
@@ -58,6 +60,9 @@ struct dyn_arch_ftrace {
#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* __ASSEMBLY__ */
+#ifdef CONFIG_DYNAMIC_FTRACE
+#define ARCH_SUPPORTS_FTRACE_OPS 1
+#endif
#endif
#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_PPC64) && !defined(__ASSEMBLY__)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index a94f155..b0dfbfe 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -1206,8 +1206,13 @@ _GLOBAL(enter_prom)
#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
- blr
+ mflr r0
+ mtctr r0
+ ld r0,LRSAVE(r1)
+ mtlr r0
+ bctr
+#ifndef CC_USING_MPROFILE_KERNEL
_GLOBAL_TOC(ftrace_caller)
/* Taken from output of objdump from lib64/glibc */
mflr r3
@@ -1229,6 +1234,81 @@ _GLOBAL(ftrace_graph_stub)
ld r0, 128(r1)
mtlr r0
addi r1, r1, 112
+#else
+_GLOBAL(ftrace_caller)
+#if defined(_CALL_ELF) && _CALL_ELF == 2
+ mflr r0
+ bl 2f
+2: mflr r12
+ mtlr r0
+ mr r0,r2 // save callee's TOC
+ addis r2,r12,(.TOC.-ftrace_caller-8)@ha
+ addi r2,r2,(.TOC.-ftrace_caller-8)@l
+#else
+ mr r0,r2
+#endif
+ ld r12,LRSAVE(r1) // get caller's address
+
+ stdu r1,-SWITCH_FRAME_SIZE(r1)
+
+ std r12, _LINK(r1)
+ SAVE_8GPRS(0,r1)
+ std r0, 24(r1) // save TOC
+ SAVE_8GPRS(8,r1)
+ SAVE_8GPRS(16,r1)
+ SAVE_8GPRS(24,r1)
+
+ LOAD_REG_IMMEDIATE(r3,function_trace_op)
+ ld r5,0(r3)
+
+ mflr r3
+ std r3, _NIP(r1)
+ std r3, 16(r1)
+ subi r3, r3, MCOUNT_INSN_SIZE
+ mfmsr r4
+ std r4, _MSR(r1)
+ mfctr r4
+ std r4, _CTR(r1)
+ mfxer r4
+ std r4, _XER(r1)
+ mr r4, r12
+ addi r6, r1 ,STACK_FRAME_OVERHEAD
+
+.globl ftrace_call
+ftrace_call:
+ bl ftrace_stub
+ nop
+
+ ld r3, _NIP(r1)
+ mtlr r3
+
+ REST_8GPRS(0,r1)
+ REST_8GPRS(8,r1)
+ REST_8GPRS(16,r1)
+ REST_8GPRS(24,r1)
+
+ addi r1, r1, SWITCH_FRAME_SIZE
+
+ ld r12, LRSAVE(r1) // get caller's address
+ mtlr r12
+ mr r2,r0 // restore callee's TOC
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ stdu r1, -112(r1)
+.globl ftrace_graph_call
+ftrace_graph_call:
+ b ftrace_graph_stub
+_GLOBAL(ftrace_graph_stub)
+ addi r1, r1, 112
+#endif
+
+ mflr r0 // move this LR to CTR
+ mtctr r0
+
+ ld r0,LRSAVE(r1) // restore callee's lr at _mcount site
+ mtlr r0
+ bctr // jump after _mcount site
+#endif /* CC_USING_MPROFILE_KERNEL */
_GLOBAL(ftrace_stub)
blr
#else
@@ -1262,6 +1342,19 @@ _GLOBAL(ftrace_stub)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
+#ifdef CC_USING_MPROFILE_KERNEL
+ // with -mprofile-kernel, parameter regs are still alive at _mcount
+ std r10, 104(r1)
+ std r9, 96(r1)
+ std r8, 88(r1)
+ std r7, 80(r1)
+ std r6, 72(r1)
+ std r5, 64(r1)
+ std r4, 56(r1)
+ std r3, 48(r1)
+ mflr r0
+ std r0, 40(r1)
+#endif
/* load r4 with local address */
ld r4, 128(r1)
subi r4, r4, MCOUNT_INSN_SIZE
@@ -1280,10 +1373,28 @@ _GLOBAL(ftrace_graph_caller)
ld r11, 112(r1)
std r3, 16(r11)
+#ifdef CC_USING_MPROFILE_KERNEL
+ ld r0, 40(r1)
+ mtctr r0
+ ld r10, 104(r1)
+ ld r9, 96(r1)
+ ld r8, 88(r1)
+ ld r7, 80(r1)
+ ld r6, 72(r1)
+ ld r5, 64(r1)
+ ld r4, 56(r1)
+ ld r3, 48(r1)
+
+ addi r1, r1, 112
+ ld r0, LRSAVE(r1)
+ mtlr r0
+ bctr
+#else
ld r0, 128(r1)
mtlr r0
addi r1, r1, 112
blr
+#endif
_GLOBAL(return_to_handler)
/* need to save return values */
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 44d4d8e..310137f 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -61,8 +61,11 @@ ftrace_modify_code(unsigned long ip, unsigned int old, unsigned int new)
return -EFAULT;
/* Make sure it is what we expect it to be */
- if (replaced != old)
+ if (replaced != old) {
+ pr_err("%p: replaced (%#x) != old (%#x)",
+ (void *)ip, replaced, old);
return -EINVAL;
+ }
/* replace the text with the new text */
if (patch_instruction((unsigned int *)ip, new))
@@ -106,14 +109,16 @@ static int
__ftrace_make_nop(struct module *mod,
struct dyn_ftrace *rec, unsigned long addr)
{
- unsigned int op;
+ unsigned int op, op0, op1, pop;
unsigned long entry, ptr;
unsigned long ip = rec->ip;
void *tramp;
/* read where this goes */
- if (probe_kernel_read(&op, (void *)ip, sizeof(int)))
+ if (probe_kernel_read(&op, (void *)ip, sizeof(int))) {
+ pr_err("Fetching opcode failed.\n");
return -EFAULT;
+ }
/* Make sure that that this is still a 24bit jump */
if (!is_bl_op(op)) {
@@ -158,10 +163,46 @@ __ftrace_make_nop(struct module *mod,
*
* Use a b +8 to jump over the load.
*/
- op = 0x48000008; /* b +8 */
- if (patch_instruction((unsigned int *)ip, op))
+ pop = 0x48000008; /* b +8 */
+
+ /*
+ * Check what is in the next instruction. We can see ld r2,40(r1), but
+ * on first pass after boot we will see mflr r0.
+ */
+ if (probe_kernel_read(&op, (void *)(ip+4), MCOUNT_INSN_SIZE)) {
+ pr_err("Fetching op failed.\n");
+ return -EFAULT;
+ }
+
+ if (op != 0xe8410028) { /* ld r2,STACK_OFFSET(r1) */
+
+ if (probe_kernel_read(&op0, (void *)(ip-8), MCOUNT_INSN_SIZE)) {
+ pr_err("Fetching op0 failed.\n");
+ return -EFAULT;
+ }
+
+ if (probe_kernel_read(&op1, (void *)(ip-4), MCOUNT_INSN_SIZE)) {
+ pr_err("Fetching op1 failed.\n");
+ return -EFAULT;
+ }
+
+ /* mflr r0 ; std r0,LRSAVE(r1) */
+ if (op0 != 0x7c0802a6 && op1 != 0xf8010010) {
+ pr_err("Unexpected instructions around bl\n"
+ "when enabling dynamic ftrace!\t"
+ "(%08x,%08x,bl,%08x)\n", op0, op1, op);
+ return -EINVAL;
+ }
+
+ /* When using -mkernel_profile there is no load to jump over */
+ pop = PPC_INST_NOP;
+ }
+
+ if (patch_instruction((unsigned int *)ip, pop)) {
+ pr_err("Patching NOP failed.\n");
return -EPERM;
+ }
return 0;
}
@@ -287,6 +328,13 @@ int ftrace_make_nop(struct module *mod,
#ifdef CONFIG_MODULES
#ifdef CONFIG_PPC64
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
+ unsigned long addr)
+{
+ return ftrace_make_call(rec, addr);
+}
+#endif
static int
__ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
@@ -306,11 +354,19 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
* The load offset is different depending on the ABI. For simplicity
* just mask it out when doing the compare.
*/
+#ifndef CC_USING_MPROFILE_KERNEL
if ((op[0] != 0x48000008) || ((op[1] & 0xffff0000) != 0xe8410000)) {
- pr_err("Unexpected call sequence: %x %x\n", op[0], op[1]);
+ pr_err("Unexpected call sequence at %p: %x %x\n",
+ ip, op[0], op[1]);
return -EINVAL;
}
-
+#else
+ /* look for patched "NOP" on ppc64 with -mprofile-kernel */
+ if (op[0] != 0x60000000) {
+ pr_err("Unexpected call at %p: %x\n", ip, op[0]);
+ return -EINVAL;
+ }
+#endif
/* If we never set up a trampoline to ftrace_caller, then bail */
if (!rec->arch.mod->arch.tramp) {
pr_err("No ftrace trampoline\n");
@@ -330,7 +386,7 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
return 0;
}
-#else
+#else /* !CONFIG_PPC64: */
static int
__ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 6838451..e62c41f 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -138,12 +138,21 @@ static u32 ppc64_stub_insns[] = {
0x4e800420 /* bctr */
};
+/* In case of _mcount calls or dynamic ftracing, Do not save the
+ * current callee's TOC (in R2) again into the original caller's stack
+ * frame during this trampoline hop. The stack frame already holds
+ * that of the original caller. _mcount and ftrace_caller will take
+ * care of this TOC value themselves.
+ */
+#define SQUASH_TOC_SAVE_INSN(trampoline_addr) \
+ (((struct ppc64_stub_entry *)(trampoline_addr))->jump[2] = PPC_INST_NOP)
+
#ifdef CONFIG_DYNAMIC_FTRACE
static u32 ppc64_stub_mask[] = {
0xffff0000,
0xffff0000,
- 0xffffffff,
+ 0x00000000,
0xffffffff,
#if !defined(_CALL_ELF) || _CALL_ELF != 2
0xffffffff,
@@ -170,6 +179,9 @@ bool is_module_trampoline(u32 *p)
if ((insna & mask) != (insnb & mask))
return false;
}
+ if (insns[2] != ppc64_stub_insns[2] &&
+ insns[2] != PPC_INST_NOP)
+ return false;
return true;
}
@@ -475,6 +487,19 @@ static unsigned long stub_for_addr(Elf64_Shdr *sechdrs,
static int restore_r2(u32 *instruction, struct module *me)
{
if (*instruction != PPC_INST_NOP) {
+
+ /* -mprofile_kernel sequence starting with
+ * mflr r0; std r0, LRSAVE(r1)
+ */
+ if (instruction[-3] == 0x7c0802a6 &&
+ instruction[-2] == 0xf8010010) {
+ /* Nothing to be done here, it's an _mcount
+ * call location and r2 will have to be
+ * restored in the _mcount function.
+ */
+ return 2;
+ };
+
pr_err("%s: Expect noop after relocate, got %08x\n",
me->name, *instruction);
return 0;
@@ -490,7 +515,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
unsigned int relsec,
struct module *me)
{
- unsigned int i;
+ unsigned int i, r2;
Elf64_Rela *rela = (void *)sechdrs[relsec].sh_addr;
Elf64_Sym *sym;
unsigned long *location;
@@ -603,8 +628,12 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
value = stub_for_addr(sechdrs, value, me);
if (!value)
return -ENOENT;
- if (!restore_r2((u32 *)location + 1, me))
+ r2 = restore_r2((u32 *)location + 1, me);
+ if (!r2)
return -ENOEXEC;
+ /* Squash the TOC saver for profiler calls */
+ if (!strcmp("_mcount", strtab+sym->st_name))
+ SQUASH_TOC_SAVE_INSN(value);
} else
value += local_entry_offset(sym);
@@ -665,6 +694,10 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
me->arch.tramp = stub_for_addr(sechdrs,
(unsigned long)ftrace_caller,
me);
+ /* ftrace_caller will take care of the TOC;
+ * do not clobber original caller's value.
+ */
+ SQUASH_TOC_SAVE_INSN(me->arch.tramp);
#endif
return 0;
--
1.8.5.6
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