Subject: Buggy commit tracked to: "Re: [PATCH 2/9] iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c"

From: Greg KH <[email-masked]>
Date: Wed, 21 Oct 2020 18:13:01 +0200

On Fri, Sep 25, 2020 at 06:51:39AM +0200, Christoph Hellwig wrote:
> From: David Laight <[email-masked]>
> 
> This lets the compiler inline it into import_iovec() generating
> much better code.
> 
> Signed-off-by: David Laight <[email-masked]>
> Signed-off-by: Christoph Hellwig <[email-masked]>
> ---
>  fs/read_write.c | 179 ------------------------------------------------
>  lib/iov_iter.c  | 176 +++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 176 insertions(+), 179 deletions(-)

Strangely, this commit causes a regression in Linus's tree right now.

I can't really figure out what the regression is, only that this commit
triggers a "large Android system binary" from working properly.  There's
no kernel log messages anywhere, and I don't have any way to strace the
thing in the testing framework, so any hints that people can provide
would be most appreciated.

thanks,

greg k-h