lkml.org 
[lkml]   [2023]   [Jan]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Is there a reason why REQ_OP_READ has to be 0?
On Mon, Jan 16, 2023 at 04:01:50PM +0000, David Howells wrote:
> Hi Jens, Christoph,
>
> Do you know if there's a reason why REQ_OP_READ has to be 0? I'm seeing a
> circumstance where a direct I/O write on a blockdev is BUG'ing in my modified
> iov_iter code because the iterator says it's a source iterator (correct), but
> the bio->bi_opf == REQ_OP_READ (which should be wrong).
>
> I thought I'd move REQ_OP_READ to, say, 4 so that I could try and see if it's
> just undefined but the kernel BUGs and then panics during boot.

There's all kind of assumptions of that from basically day 1 of
Linux. The most obvious one is in op_is_write, but I'm pretty sure
there are more hidden somewhere.

\
 
 \ /
  Last update: 2023-03-26 23:43    [W:0.066 / U:0.252 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site