Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1452984 > unrolled thread
| Started by | Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> |
|---|---|
| First post | 2016-08-01 06:40 +0200 |
| Last post | 2016-08-02 15:20 +0200 |
| Articles | 3 — 3 participants |
Back to article view | Back to linux.kernel
[PATCH 1/2 v4] perf sched: fix wrong conversion of task state Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> - 2016-08-01 06:40 +0200
Re: [PATCH 1/2 v4] perf sched: fix wrong conversion of task state David Ahern <dsahern@gmail.com> - 2016-08-01 16:00 +0200
Re: [PATCH 1/2 v4] perf sched: fix wrong conversion of task state Masami Hiramatsu <mhiramat@kernel.org> - 2016-08-02 15:20 +0200
| From | Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> |
|---|---|
| Date | 2016-08-01 06:40 +0200 |
| Subject | [PATCH 1/2 v4] perf sched: fix wrong conversion of task state |
| Message-ID | <s1dbb-1vs-15@gated-at.bofh.it> |
Currently sched_out_state() converts the prev_state u64 bitmask to a char
using the bitmask as an index, which may cause invalid memory access.
This fixes the issue by using the __ffs() returned value as an index.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Fixes: cdce9d738b91e ("perf sched: Add sched latency profiling")
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
---
Changes from v3:
Added Fixes:
Split the patch into 2 pieces.
tools/perf/builtin-sched.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 0dfe8df..ce9bef6 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -897,9 +897,10 @@ static int thread_atoms_insert(struct perf_sched *sched, struct thread *thread)
static char sched_out_state(u64 prev_state)
{
- const char *str = TASK_STATE_TO_CHAR_STR;
+ const char str[] = TASK_STATE_TO_CHAR_STR;
+ unsigned int bit = prev_state ? __ffs(prev_state) + 1 : 0;
- return str[prev_state];
+ return bit < ARRAY_SIZE(str) - 1 ? str[bit] : '?';
}
static int
--
2.7.4
[toc] | [next] | [standalone]
| From | David Ahern <dsahern@gmail.com> |
|---|---|
| Date | 2016-08-01 16:00 +0200 |
| Message-ID | <s1lV7-73w-11@gated-at.bofh.it> |
| In reply to | #1452984 |
On 7/31/16 10:30 PM, Tomoki Sekiyama wrote:
> Currently sched_out_state() converts the prev_state u64 bitmask to a char
> using the bitmask as an index, which may cause invalid memory access.
> This fixes the issue by using the __ffs() returned value as an index.
>
> Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
> Fixes: cdce9d738b91e ("perf sched: Add sched latency profiling")
> Cc: Jiri Olsa <jolsa@kernel.org>
> Cc: David Ahern <dsahern@gmail.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> Changes from v3:
> Added Fixes:
> Split the patch into 2 pieces.
>
> tools/perf/builtin-sched.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
> index 0dfe8df..ce9bef6 100644
> --- a/tools/perf/builtin-sched.c
> +++ b/tools/perf/builtin-sched.c
> @@ -897,9 +897,10 @@ static int thread_atoms_insert(struct perf_sched *sched, struct thread *thread)
>
> static char sched_out_state(u64 prev_state)
> {
> - const char *str = TASK_STATE_TO_CHAR_STR;
> + const char str[] = TASK_STATE_TO_CHAR_STR;
> + unsigned int bit = prev_state ? __ffs(prev_state) + 1 : 0;
>
> - return str[prev_state];
> + return bit < ARRAY_SIZE(str) - 1 ? str[bit] : '?';
> }
>
> static int
>
Acked-by: David Ahern <dsahern@gmail.com>
[toc] | [prev] | [next] | [standalone]
| From | Masami Hiramatsu <mhiramat@kernel.org> |
|---|---|
| Date | 2016-08-02 15:20 +0200 |
| Message-ID | <s1HLZ-4Xn-63@gated-at.bofh.it> |
| In reply to | #1452984 |
On Mon, 1 Aug 2016 13:30:25 +0900
Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> wrote:
> Currently sched_out_state() converts the prev_state u64 bitmask to a char
> using the bitmask as an index, which may cause invalid memory access.
> This fixes the issue by using the __ffs() returned value as an index.
OK, looks good to me:)
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Thanks!
>
> Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
> Fixes: cdce9d738b91e ("perf sched: Add sched latency profiling")
> Cc: Jiri Olsa <jolsa@kernel.org>
> Cc: David Ahern <dsahern@gmail.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> Changes from v3:
> Added Fixes:
> Split the patch into 2 pieces.
>
> tools/perf/builtin-sched.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
> index 0dfe8df..ce9bef6 100644
> --- a/tools/perf/builtin-sched.c
> +++ b/tools/perf/builtin-sched.c
> @@ -897,9 +897,10 @@ static int thread_atoms_insert(struct perf_sched *sched, struct thread *thread)
>
> static char sched_out_state(u64 prev_state)
> {
> - const char *str = TASK_STATE_TO_CHAR_STR;
> + const char str[] = TASK_STATE_TO_CHAR_STR;
> + unsigned int bit = prev_state ? __ffs(prev_state) + 1 : 0;
>
> - return str[prev_state];
> + return bit < ARRAY_SIZE(str) - 1 ? str[bit] : '?';
> }
>
> static int
> --
> 2.7.4
>
--
Masami Hiramatsu <mhiramat@kernel.org>
[toc] | [prev] | [standalone]
Back to top | Article view | linux.kernel
csiph-web