On 6/20/2020 7:22 AM, Jens Axboe wrote:
On 6/20/20 3:59 AM, Pavel Begunkov wrote:
On 20/06/2020 02:57, Bijan Mottahedeh wrote:
If current->mm is not set in SQPOLL mode, then use ctx->sqo_mm;
otherwise fail thre request.
io_sq_thread_acquire_mm() called from io_async_buf_retry() should've
guaranteed presence of current->mm. Though, the problem could be in
"io_op_defs[req->opcode].needs_mm" check there, which is done only
for the first request in a link.
Right, Bijan are you sure this isn't fixed by one of the fixes that
went upstream yesterday:
commit 9d8426a09195e2dcf2aa249de2aaadd792d491c7
Author: Jens Axboe <axboe@xxxxxxxxx>
Date: Tue Jun 16 18:42:49 2020 -0600
io_uring: acquire 'mm' for task_work for SQPOLL
I was running next-20200618.
Both 0618 and 0620 contain
io_uring: acquire 'mm' for task_work for SQPOLL
The commit
io_uring: support true async buffered reads, if file provides it
however is different in 0618 and 0620, the 0618 version is missing the call
if (!io_sq_thread_acquire_mm(ctx, req)) {
in io_async_buf_retry().
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/fs/io_uring.c?h=next-20200618&id=a3bb0c190b85781d7857b7a55cb9cefded5f527b
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/fs/io_uring.c?h=next-20200622&id=3ad1d68c04bf9555942b63b5aba31e446fdcf355
I pulled the 0622 and the read-write test runs fine.
--bijan
