[f2fs-dev,v2] f2fs: fix uninitialized skipped_gc_rwsem

Commit Message

Yonggil Song Feb. 16, 2023, 7:44 a.m. UTC

When f2fs skipped a gc round during victim migration, there was a bug which
would skip all upcoming gc rounds unconditionally because skipped_gc_rwsem
was not initialized. It fixes the bug by correctly initializing the
skipped_gc_rwsem inside the gc loop.

Fixes: 3db1de0e582c ("f2fs: change the current atomic write way")
Cc: [e-mail]
Signed-off-by: Yonggil Song <[e-mail]>

Comments

Greg KH Feb. 16, 2023, 7:46 a.m. UTC | #1

On Thu, Feb 16, 2023 at 04:44:27PM +0900, Yonggil Song wrote:
> When f2fs skipped a gc round during victim migration, there was a bug which
> would skip all upcoming gc rounds unconditionally because skipped_gc_rwsem
> was not initialized. It fixes the bug by correctly initializing the
> skipped_gc_rwsem inside the gc loop.
> 
> Fixes: 3db1de0e582c ("f2fs: change the current atomic write way")
> Cc: [e-mail]
> Signed-off-by: Yonggil Song <[e-mail]>
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index b22f49a6f128..81d326abaac1 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -1786,8 +1786,8 @@ int f2fs_gc(struct f2fs_sb_info *sbi, struct f2fs_gc_control *gc_control)
>  				prefree_segments(sbi));
>  
>  	cpc.reason = __get_cp_reason(sbi);
> -	sbi->skipped_gc_rwsem = 0;
>  gc_more:
> +	sbi->skipped_gc_rwsem = 0;
>  	if (unlikely(!(sbi->sb->s_flags & SB_ACTIVE))) {
>  		ret = -EINVAL;
>  		goto stop;
> -- 
> 2.34.1

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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thanks,

greg k-h's patch email bot

[e-mail] March 13, 2023, 8:20 p.m. UTC | #2

Hello:

This patch was applied to jaegeuk/f2fs.git (dev)
by Jaegeuk Kim <[e-mail]>:

On Thu, 16 Feb 2023 16:44:27 +0900 you wrote:
> When f2fs skipped a gc round during victim migration, there was a bug which
> would skip all upcoming gc rounds unconditionally because skipped_gc_rwsem
> was not initialized. It fixes the bug by correctly initializing the
> skipped_gc_rwsem inside the gc loop.
> 
> Fixes: 3db1de0e582c ("f2fs: change the current atomic write way")
> Cc: [e-mail]
> Signed-off-by: Yonggil Song <[e-mail]>

Here is the summary with links:
  - [f2fs-dev,v2] f2fs: fix uninitialized skipped_gc_rwsem
    https://git.kernel.org/jaegeuk/f2fs/c/196036c45f8c

You are awesome, thank you!

Patch

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index b22f49a6f128..81d326abaac1 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1786,8 +1786,8 @@  int f2fs_gc(struct f2fs_sb_info *sbi, struct f2fs_gc_control *gc_control)
 				prefree_segments(sbi));
 
 	cpc.reason = __get_cp_reason(sbi);
-	sbi->skipped_gc_rwsem = 0;
 gc_more:
+	sbi->skipped_gc_rwsem = 0;
 	if (unlikely(!(sbi->sb->s_flags & SB_ACTIVE))) {
 		ret = -EINVAL;
 		goto stop;