Re: [PATCH 17/17] mmc: pass queue_limits to blk_mq_alloc_disk

Geert Uytterhoeven
2024-02-21T09:37:53Z

Hi Christoph,

On Wed, Feb 21, 2024 at 6:44 AM Christoph Hellwig <hch@lst.de> wrote:
> On Tue, Feb 20, 2024 at 11:01:05PM +0100, Geert Uytterhoeven wrote:
> > On Thu, Feb 15, 2024 at 9:16 AM Christoph Hellwig <hch@lst.de> wrote:
> > > Pass the queue limit set at initialization time directly to
> > > blk_mq_alloc_disk instead of updating it right after the allocation.
> > >
> > > This requires refactoring the code a bit so that what was mmc_setup_queue
> > > before also allocates the gendisk now and actually sets all limits.
> > >
> > > Signed-off-by: Christoph Hellwig <hch@lst.de>
> >
> > Thanks for your patch, which is now commit 616f876617927732 ("mmc: pass
> > queue_limits to blk_mq_alloc_disk") in block/for-next.
> >
> > I have bisected the following failure on White-Hawk (also seen on
> > other R-Car Gen3/4 systems) to this commit:
> >
> > renesas_sdhi_internal_dmac ee140000.mmc: mmc0 base at
> > 0x00000000ee140000, max clock rate 200 MHz
> > mmc0: new HS400 MMC card at address 0001
> > ------------[ cut here ]------------
> > WARNING: CPU: 1 PID: 20 at block/blk-settings.c:202
> > blk_validate_limits+0x12c/0x1e0
>
> This is:
>
> if (lim->virt_boundary_mask) {
> if (WARN_ON_ONCE(lim->max_segment_size &&
> lim->max_segment_size != UINT_MAX))
> return -EINVAL;
>
> so we end up here with both a virt_boundary_mask and a
> max_segment_size set, which is rather bogus. I think the
> problem is the order of check in the core blk_validate_limits
> that artificially causes this. Can you try this patch?

Thanks, good thinking, as that fixed the issue for me!

Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds