Fix iwlwifi load failure on some hardware (rbhz 1607092)

2 files changed, 131 insertions, 0 deletions

diff --git a/Revert-iommu-intel-iommu-Enable-CONFIG_DMA_DIRECT_OP.patch b/Revert-iommu-intel-iommu-Enable-CONFIG_DMA_DIRECT_OP.patch
new file mode 100644
index 000000000..46212341f
--- /dev/null
+++ b/Revert-iommu-intel-iommu-Enable-CONFIG_DMA_DIRECT_OP.patch
@@ -0,0 +1,125 @@
+From 3c16e0cc4ace8bd838bf234caead5a766b07fe9d Mon Sep 17 00:00:00 2001
+From: Christoph Hellwig <hch@lst.de>
+Date: Thu, 5 Jul 2018 13:29:55 -0600
+Subject: [PATCH] Revert "iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and
+ clean up intel_{alloc,free}_coherent()"
+
+This commit may cause a less than required dma mask to be used for
+some allocations, which apparently leads to module load failures for
+iwlwifi sometimes.
+
+This reverts commit d657c5c73ca987214a6f9436e435b34fc60f332a.
+
+Signed-off-by: Christoph Hellwig <hch@lst.de>
+Reported-by: Fabio Coatti <fabio.coatti@gmail.com>
+Tested-by: Fabio Coatti <fabio.coatti@gmail.com>
+Signed-off-by: Jeremy Cline <jcline@redhat.com>
+---
+ drivers/iommu/Kconfig       |  1 -
+ drivers/iommu/intel-iommu.c | 62 +++++++++++++++++++++++++++----------
+ 2 files changed, 46 insertions(+), 17 deletions(-)
+
+diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
+index b38798cc5288..f3a21343e636 100644
+--- a/drivers/iommu/Kconfig
++++ b/drivers/iommu/Kconfig
+@@ -142,7 +142,6 @@ config DMAR_TABLE
+ config INTEL_IOMMU
+ 	bool "Support for Intel IOMMU using DMA Remapping Devices"
+ 	depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
+-	select DMA_DIRECT_OPS
+ 	select IOMMU_API
+ 	select IOMMU_IOVA
+ 	select DMAR_TABLE
+diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
+index 749d8f235346..6392a4964fc5 100644
+--- a/drivers/iommu/intel-iommu.c
++++ b/drivers/iommu/intel-iommu.c
+@@ -31,7 +31,6 @@
+ #include <linux/pci.h>
+ #include <linux/dmar.h>
+ #include <linux/dma-mapping.h>
+-#include <linux/dma-direct.h>
+ #include <linux/mempool.h>
+ #include <linux/memory.h>
+ #include <linux/cpu.h>
+@@ -3709,30 +3708,61 @@ static void *intel_alloc_coherent(struct device *dev, size_t size,
+ 				  dma_addr_t *dma_handle, gfp_t flags,
+ 				  unsigned long attrs)
+ {
+-	void *vaddr;
++	struct page *page = NULL;
++	int order;
+ 
+-	vaddr = dma_direct_alloc(dev, size, dma_handle, flags, attrs);
+-	if (iommu_no_mapping(dev) || !vaddr)
+-		return vaddr;
++	size = PAGE_ALIGN(size);
++	order = get_order(size);
+ 
+-	*dma_handle = __intel_map_single(dev, virt_to_phys(vaddr),
+-			PAGE_ALIGN(size), DMA_BIDIRECTIONAL,
+-			dev->coherent_dma_mask);
+-	if (!*dma_handle)
+-		goto out_free_pages;
+-	return vaddr;
++	if (!iommu_no_mapping(dev))
++		flags &= ~(GFP_DMA | GFP_DMA32);
++	else if (dev->coherent_dma_mask < dma_get_required_mask(dev)) {
++		if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
++			flags |= GFP_DMA;
++		else
++			flags |= GFP_DMA32;
++	}
++
++	if (gfpflags_allow_blocking(flags)) {
++		unsigned int count = size >> PAGE_SHIFT;
++
++		page = dma_alloc_from_contiguous(dev, count, order, flags);
++		if (page && iommu_no_mapping(dev) &&
++		    page_to_phys(page) + size > dev->coherent_dma_mask) {
++			dma_release_from_contiguous(dev, page, count);
++			page = NULL;
++		}
++	}
++
++	if (!page)
++		page = alloc_pages(flags, order);
++	if (!page)
++		return NULL;
++	memset(page_address(page), 0, size);
++
++	*dma_handle = __intel_map_single(dev, page_to_phys(page), size,
++					 DMA_BIDIRECTIONAL,
++					 dev->coherent_dma_mask);
++	if (*dma_handle)
++		return page_address(page);
++	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
++		__free_pages(page, order);
+ 
+-out_free_pages:
+-	dma_direct_free(dev, size, vaddr, *dma_handle, attrs);
+ 	return NULL;
+ }
+ 
+ static void intel_free_coherent(struct device *dev, size_t size, void *vaddr,
+ 				dma_addr_t dma_handle, unsigned long attrs)
+ {
+-	if (!iommu_no_mapping(dev))
+-		intel_unmap(dev, dma_handle, PAGE_ALIGN(size));
+-	dma_direct_free(dev, size, vaddr, dma_handle, attrs);
++	int order;
++	struct page *page = virt_to_page(vaddr);
++
++	size = PAGE_ALIGN(size);
++	order = get_order(size);
++
++	intel_unmap(dev, dma_handle, size);
++	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
++		__free_pages(page, order);
+ }
+ 
+ static void intel_unmap_sg(struct device *dev, struct scatterlist *sglist,
+-- 
+2.17.1
+
diff --git a/kernel.spec b/kernel.spec
index 6f6265c8d..22817b63e 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -674,6 +674,9 @@ Patch523: 0001-xfs-More-robust-inode-extent-count-validation.patch
 # i686 patch that will eventually be 4.17.8
 Patch527: mm-don-t-do-zero_resv_unavail-if-memmap-is-not-allocated.patch
 
+# rbhz 1607092
+Patch528: Revert-iommu-intel-iommu-Enable-CONFIG_DMA_DIRECT_OP.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -1923,6 +1926,9 @@ fi
 #
 #
 %changelog
+* Mon Jul 23 2018 Jeremy Cline <jeremy@jcline.org>
+- Fix iwlwifi module load failure (rhbz 1607092)
+
 * Tue Jul 17 2018 Justin M. Forbes <jforbes@fedoraproject.org> - 4.17.7-200
 - Linux v4.17.7