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FAILED: patch "[PATCH] iommu/io-pgtable-arm-v7s: request DMA32 memory, and improve" failed to apply to 4.19-stable tree

PATCH [email protected] 1 participant 1 message Mar 30, 2019

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The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 0a352554da69b02f75ca3389c885c741f1f63235 Mon Sep 17 00:00:00 2001
From: Nicolas Boichat <[email protected]>
Date: Thu, 28 Mar 2019 20:43:46 -0700
Subject: [PATCH] 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/[email protected] open here
Fixes ad67f5a6545f ("arm64: replace ZONE_DMA with ZONE_DMA32")
Signed-off-by Nicolas Boichat <[email protected]>
Acked-by Will Deacon <[email protected]>
Cc Christoph Hellwig <[email protected]>
Cc Christoph Lameter <[email protected]>
Cc David Rientjes <[email protected]>
Cc Hsin-Yi Wang <[email protected]>
Cc Huaisheng Ye <[email protected]>
Cc Joerg Roedel <[email protected]>
Cc Joonsoo Kim <[email protected]>
Cc Matthew Wilcox <[email protected]>
Cc Matthias Brugger <[email protected]>
Cc Mel Gorman <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Mike Rapoport <[email protected]>
Cc Pekka Enberg <[email protected]>
Cc Robin Murphy <[email protected]>
Cc Sasha Levin <[email protected]>
Cc Tomasz Figa <[email protected]>
Cc Vlastimil Babka <[email protected]>
Cc Yingjoe Chen <[email protected]>
Cc Yong Wu <[email protected]>
Cc <[email protected]>
Signed-off-by Andrew Morton <[email protected]>
Signed-off-by Linus Torvalds <[email protected]>
drivers/iommu/io-pgtable-arm-v7s.c +15 -4
index f101afc315ab..9a8a8870e267 100644
@@ -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 lvl, gfp_t gfp,
 	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_pgtable(struct io_pgtable_cfg *cfg,
 	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;