Hi Ming, On Wed, Apr 24, 2024 at 2:41 PM Ming Lei <ming.lei@xxxxxxxxxx> wrote: > On Wed, Apr 24, 2024 at 12:26:26PM +0200, Geert Uytterhoeven wrote: > > On Sun, 7 Apr 2024, Ming Lei wrote: > > > When one stacking device is over one device with virt_boundary_mask and > > > another one with max segment size, the stacking device have both limits > > > set. This way is allowed before d690cb8ae14b ("block: add an API to > > > atomically update queue limits"). > > > > > > Relax the limit so that we won't break such kind of stacking setting. > > > > > > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218687 > > > Reported-by: janpieter.sollie@xxxxxxxxx > > > Fixes: d690cb8ae14b ("block: add an API to atomically update queue limits") > > > Link: https://lore.kernel.org/linux-block/ZfGl8HzUpiOxCLm3@fedora/ > > > Cc: Christoph Hellwig <hch@xxxxxx> > > > Cc: Mike Snitzer <snitzer@xxxxxxxxxx> > > > Cc: dm-devel@xxxxxxxxxxxxxxx > > > Cc: Song Liu <song@xxxxxxxxxx> > > > Cc: linux-raid@xxxxxxxxxxxxxxx > > > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > > > > Thanks for your patch, which is now commit b561ea56a26415bf ("block: > > allow device to have both virt_boundary_mask and max segment size") in > > v6.9-rc4. > > > > With CONFIG_DMA_API_DEBUG_SG=y and IOMMU support enabled, this causes a > > warning on R-Car Gen3/Gen4 platforms: > > > > DMA-API: renesas_sdhi_internal_dmac ee160000.mmc: mapping sg segment longer than device claims to support [len=86016] [max=65536] > > WARNING: CPU: 1 PID: 281 at kernel/dma/debug.c:1178 debug_dma_map_sg+0x2ac/0x330 > > > > Reverting this commit, or disabling IOMMU support fixes the issue. > > Can you test the following patch? > > > diff --git a/block/blk-settings.c b/block/blk-settings.c > index 8e1d7ed52fef..ebba05a2bc7f 100644 > --- a/block/blk-settings.c > +++ b/block/blk-settings.c > @@ -188,7 +188,10 @@ static int blk_validate_limits(struct queue_limits *lim) > * bvec and lower layer bio splitting is supposed to handle the two > * correctly. > */ > - if (!lim->virt_boundary_mask) { > + if (lim->virt_boundary_mask) { > + if (!lim->max_segment_size) > + lim->max_segment_size = UINT_MAX; > + } else { > /* > * The maximum segment size has an odd historic 64k default that > * drivers probably should override. Just like the I/O size we Thanks, that works for me (both with/without IOMMU support)! Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx 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