Re: [GIT PULL] Btrfs updates for 5.16

[David Sterba]

On Tue, Nov 02, 2021 at 08:08:22AM +0800, Qu Wenruo wrote:
> On 2021/11/2 04:03, Linus Torvalds wrote:
> > On Mon, Nov 1, 2021 at 9:46 AM David Sterba <dsterba@xxxxxxxx> wrote:
> > it's correct.
> >
> > Or maybe I messed up entirely.
> >
> > I did end up comparing it to your other branch too, but that was
> > equally as messy, apart from the "ok, I can mindlessly just take your
> > side".
> >
> > And it was fairly different from what I had done in my merge
> > resolution, so who knows.
> >
> > ANYWAY. What I'm trying to say is that you should look very very
> > carefully at commits
> >
> >    2cf3f8133bda ("btrfs: fix lzo_decompress_bio() kmap leakage")
> 
> Since I'm doing the revert manually for lzo part, I double checked the code.
> 
> It turns out, your fix is the same as the original version I sent to
> David (although not through the mail list).
> Full patch attached.
> 
> @@ -345,8 +358,9 @@ int lzo_decompress_bio(struct list_head *ws, struct
> compressed_bio *cb)
>   		       (cur_in + LZO_LEN - 1) / sectorsize);
>   		cur_page = cb->compressed_pages[cur_in / PAGE_SIZE];
>   		ASSERT(cur_page);
> -		seg_len = read_compress_length(page_address(cur_page) +
> -					       offset_in_page(cur_in));
> +		kaddr = kmap(cur_page);
> +		seg_len = read_compress_length(kaddr + offset_in_page(cur_in));
> +		kunmap(cur_page);
>   		cur_in += LZO_LEN;
> 
> Thus it looks like by somehow my version is not applied?

Yeah, I had a look what you sent me, that version was correct. The
mistake was on my side, a copy&paste error, sorry.