On Wed, Mar 20, 2019 at 2:37 AM <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > > The patch titled > Subject: iommu/io-pgtable-arm-v7s: request DMA32 memory, and improve debugging > has been added to the -mm tree. Its filename is > iommu-io-pgtable-arm-v7s-request-dma32-memory-and-improve-debugging.patch > > This patch should soon appear at > http://ozlabs.org/~akpm/mmots/broken-out/iommu-io-pgtable-arm-v7s-request-dma32-memory-and-improve-debugging.patch > and later at > http://ozlabs.org/~akpm/mmotm/broken-out/iommu-io-pgtable-arm-v7s-request-dma32-memory-and-improve-debugging.patch > > Before you just go and hit "reply", please: > a) Consider who else should be cc'ed > b) Prefer to cc a suitable mailing list as well > c) Ideally: find the original patch on the mailing list and do a > reply-to-all to that, adding suitable additional cc's > > *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** > > The -mm tree is included into linux-next and is updated > there every 3-4 working days > > ------------------------------------------------------ > From: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> > Subject: iommu/io-pgtable-arm-v7s: request DMA32 memory, and improve debugging > > IOMMUs using ARMv7 short-descriptor format require page tables (level 1 > and 2) to be allocated within the first 4GB of RAM, even on 64-bit > systems. > > For level 1/2 pages, ensure GFP_DMA32 is used if CONFIG_ZONE_DMA32 is > defined (e.g. on arm64 platforms). > > For level 2 pages, allocate a slab cache in SLAB_CACHE_DMA32. Note that > we do not explicitly pass GFP_DMA[32] to kmem_cache_zalloc, as this is not > strictly necessary, and would cause a warning in mm/sl*b.c, as we did not > update GFP_SLAB_BUG_MASK. > > Also, print an error when the physical address does not fit in > 32-bit, to make debugging easier in the future. > > Link: http://lkml.kernel.org/r/20181210011504.122604-3-drinkcat@xxxxxxxxxxxx > Fixes: ad67f5a6545f ("arm64: replace ZONE_DMA with ZONE_DMA32") > Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> This was acked (twice! ,-)) by Will (https://patchwork.kernel.org/patch/10720489/): Acked-by: Will Deacon <will.deacon@xxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> > Cc: Christoph Lameter <cl@xxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> > Cc: Huaisheng Ye <yehs1@xxxxxxxxxx> > Cc: Joerg Roedel <joro@xxxxxxxxxx> > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> > Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxx> > Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: Robin Murphy <robin.murphy@xxxxxxx> > Cc: Sasha Levin <Alexander.Levin@xxxxxxxxxxxxx> > Cc: Tomasz Figa <tfiga@xxxxxxxxxx> > Cc: Vlastimil Babka <vbabka@xxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx> > Cc: Yong Wu <yong.wu@xxxxxxxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > drivers/iommu/io-pgtable-arm-v7s.c | 19 +++++++++++++++---- > 1 file changed, 15 insertions(+), 4 deletions(-) > > --- a/drivers/iommu/io-pgtable-arm-v7s.c~iommu-io-pgtable-arm-v7s-request-dma32-memory-and-improve-debugging > +++ a/drivers/iommu/io-pgtable-arm-v7s.c > @@ -160,6 +160,14 @@ > > #define ARM_V7S_TCR_PD1 BIT(5) > > +#ifdef CONFIG_ZONE_DMA32 > +#define ARM_V7S_TABLE_GFP_DMA GFP_DMA32 > +#define ARM_V7S_TABLE_SLAB_FLAGS SLAB_CACHE_DMA32 > +#else > +#define ARM_V7S_TABLE_GFP_DMA GFP_DMA > +#define ARM_V7S_TABLE_SLAB_FLAGS SLAB_CACHE_DMA > +#endif > + > typedef u32 arm_v7s_iopte; > > static bool selftest_running; > @@ -197,13 +205,16 @@ static void *__arm_v7s_alloc_table(int l > void *table = NULL; > > if (lvl == 1) > - table = (void *)__get_dma_pages(__GFP_ZERO, get_order(size)); > + table = (void *)__get_free_pages( > + __GFP_ZERO | ARM_V7S_TABLE_GFP_DMA, get_order(size)); > else if (lvl == 2) > - table = kmem_cache_zalloc(data->l2_tables, gfp | GFP_DMA); > + table = kmem_cache_zalloc(data->l2_tables, gfp); > phys = virt_to_phys(table); > - if (phys != (arm_v7s_iopte)phys) > + if (phys != (arm_v7s_iopte)phys) { > /* Doesn't fit in PTE */ > + dev_err(dev, "Page table does not fit in PTE: %pa", &phys); > goto out_free; > + } > if (table && !(cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA)) { > dma = dma_map_single(dev, table, size, DMA_TO_DEVICE); > if (dma_mapping_error(dev, dma)) > @@ -733,7 +744,7 @@ static struct io_pgtable *arm_v7s_alloc_ > data->l2_tables = kmem_cache_create("io-pgtable_armv7s_l2", > ARM_V7S_TABLE_SIZE(2), > ARM_V7S_TABLE_SIZE(2), > - SLAB_CACHE_DMA, NULL); > + ARM_V7S_TABLE_SLAB_FLAGS, NULL); > if (!data->l2_tables) > goto out_free_data; > > _ > > Patches currently in -mm which might be from drinkcat@xxxxxxxxxxxx are > > mm-add-support-for-kmem-caches-in-dma32-zone.patch > iommu-io-pgtable-arm-v7s-request-dma32-memory-and-improve-debugging.patch > mm-add-sys-kernel-slab-cache-cache_dma32.patch >
