Re: [PATCH 1/2] kprobes: Allow architectures to override optinsn page allocation
On Thu, 13 May 2021 03:04:51 +0800 kernel test robot wrote: > Hi Christophe, > > I love your patch! Perhaps something to improve: > > [auto build test WARNING on powerpc/next] > [also build test WARNING on linus/master v5.13-rc1 next-20210512] > [If your patch is applied to the wrong git tree, kindly drop us a note. > And when submitting patch, we suggest to use '--base' as documented in > https://git-scm.com/docs/git-format-patch] > > url: > https://github.com/0day-ci/linux/commits/Christophe-Leroy/kprobes-Allow-architectures-to-override-optinsn-page-allocation/20210512-223121 > base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next > config: i386-randconfig-r012-20210512 (attached as .config) > compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 > reproduce (this is a W=1 build): > # > https://github.com/0day-ci/linux/commit/2a1f135a9ce3c4d86d3bdefed561aa17760f430f > git remote add linux-review https://github.com/0day-ci/linux > git fetch --no-tags linux-review > Christophe-Leroy/kprobes-Allow-architectures-to-override-optinsn-page-allocation/20210512-223121 > git checkout 2a1f135a9ce3c4d86d3bdefed561aa17760f430f > # save the attached .config to linux build tree > make W=1 W=1 ARCH=i386 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot > > All warnings (new ones prefixed by >>): > > >> kernel/kprobes.c:324:14: warning: no previous prototype for > >> 'alloc_optinsn_page' [-Wmissing-prototypes] > 324 | void __weak *alloc_optinsn_page(void) > | ^~ > >> kernel/kprobes.c:329:13: warning: no previous prototype for > >> 'free_optinsn_page' [-Wmissing-prototypes] > 329 | void __weak free_optinsn_page(void *page) > | ^ Ah, we need a prototype for those in include/linux/kprobes.h as same as alloc_insn_page() and free_insn_page(). Thank you, -- Masami Hiramatsu
Re: [PATCH 1/2] kprobes: Allow architectures to override optinsn page allocation
On Wed, 12 May 2021 14:29:26 + (UTC)
Christophe Leroy wrote:
> Some architectures like powerpc require a non standard
> allocation of optinsn page, because module pages are
> too far from the kernel for direct branches.
>
> Define weak alloc_optinsn_page() and free_optinsn_page(), that
> fall back on alloc_insn_page() and free_insn_page() when not
> overriden by the architecture.
>
Looks good to me :)
Acked-by: Masami Hiramatsu
> Suggested-by: Masami Hiramatsu
> Signed-off-by: Christophe Leroy
> ---
> kernel/kprobes.c | 14 --
> 1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 745f08fdd7a6..8c0a6fdef771 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -321,11 +321,21 @@ int kprobe_cache_get_kallsym(struct kprobe_insn_cache
> *c, unsigned int *symnum,
> }
>
> #ifdef CONFIG_OPTPROBES
> +void __weak *alloc_optinsn_page(void)
> +{
> + return alloc_insn_page();
> +}
> +
> +void __weak free_optinsn_page(void *page)
> +{
> + free_insn_page(page);
> +}
> +
> /* For optimized_kprobe buffer */
> struct kprobe_insn_cache kprobe_optinsn_slots = {
> .mutex = __MUTEX_INITIALIZER(kprobe_optinsn_slots.mutex),
> - .alloc = alloc_insn_page,
> - .free = free_insn_page,
> + .alloc = alloc_optinsn_page,
> + .free = free_optinsn_page,
> .sym = KPROBE_OPTINSN_PAGE_SYM,
> .pages = LIST_HEAD_INIT(kprobe_optinsn_slots.pages),
> /* .insn_size is initialized later */
> --
> 2.25.0
>
--
Masami Hiramatsu
Re: [PATCH 1/2] kprobes: Allow architectures to override optinsn page allocation
Hi Christophe,
I love your patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on linus/master v5.13-rc1 next-20210512]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url:
https://github.com/0day-ci/linux/commits/Christophe-Leroy/kprobes-Allow-architectures-to-override-optinsn-page-allocation/20210512-223121
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: i386-randconfig-r012-20210512 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
#
https://github.com/0day-ci/linux/commit/2a1f135a9ce3c4d86d3bdefed561aa17760f430f
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review
Christophe-Leroy/kprobes-Allow-architectures-to-override-optinsn-page-allocation/20210512-223121
git checkout 2a1f135a9ce3c4d86d3bdefed561aa17760f430f
# save the attached .config to linux build tree
make W=1 W=1 ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot
All warnings (new ones prefixed by >>):
>> kernel/kprobes.c:324:14: warning: no previous prototype for
>> 'alloc_optinsn_page' [-Wmissing-prototypes]
324 | void __weak *alloc_optinsn_page(void)
| ^~
>> kernel/kprobes.c:329:13: warning: no previous prototype for
>> 'free_optinsn_page' [-Wmissing-prototypes]
329 | void __weak free_optinsn_page(void *page)
| ^
vim +/alloc_optinsn_page +324 kernel/kprobes.c
322
323 #ifdef CONFIG_OPTPROBES
> 324 void __weak *alloc_optinsn_page(void)
325 {
326 return alloc_insn_page();
327 }
328
> 329 void __weak free_optinsn_page(void *page)
330 {
331 free_insn_page(page);
332 }
333
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org
.config.gz
Description: application/gzip
[PATCH 1/2] kprobes: Allow architectures to override optinsn page allocation
Some architectures like powerpc require a non standard
allocation of optinsn page, because module pages are
too far from the kernel for direct branches.
Define weak alloc_optinsn_page() and free_optinsn_page(), that
fall back on alloc_insn_page() and free_insn_page() when not
overriden by the architecture.
Suggested-by: Masami Hiramatsu
Signed-off-by: Christophe Leroy
---
kernel/kprobes.c | 14 --
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 745f08fdd7a6..8c0a6fdef771 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -321,11 +321,21 @@ int kprobe_cache_get_kallsym(struct kprobe_insn_cache *c,
unsigned int *symnum,
}
#ifdef CONFIG_OPTPROBES
+void __weak *alloc_optinsn_page(void)
+{
+ return alloc_insn_page();
+}
+
+void __weak free_optinsn_page(void *page)
+{
+ free_insn_page(page);
+}
+
/* For optimized_kprobe buffer */
struct kprobe_insn_cache kprobe_optinsn_slots = {
.mutex = __MUTEX_INITIALIZER(kprobe_optinsn_slots.mutex),
- .alloc = alloc_insn_page,
- .free = free_insn_page,
+ .alloc = alloc_optinsn_page,
+ .free = free_optinsn_page,
.sym = KPROBE_OPTINSN_PAGE_SYM,
.pages = LIST_HEAD_INIT(kprobe_optinsn_slots.pages),
/* .insn_size is initialized later */
--
2.25.0
