5.15-stable patches

added patches:
	xen-swiotlb-relax-alignment-requirements.patch

diff --git a/queue-5.15/series b/queue-5.15/series
index 92c09f2d0536bdd60ac8fff8276f22c58c2c5c0e..c1bf4b7e4fa840c3832603d6867a1322b2ef0d73 100644 (file)
--- a/queue-5.15/series
+++ b/queue-5.15/series
@@ -210,3 +210,4 @@ x86-pvh-call-c-code-via-the-kernel-virtual-mapping.patch
 powerpc-rtas-prevent-spectre-v1-gadget-construction-in-sys_rtas.patch
 phy-tegra-xusb-fix-return-value-of-tegra_xusb_find_port_node-function.patch
 wifi-ath10k-avoid-null-pointer-error-during-sdio-remove.patch
+xen-swiotlb-relax-alignment-requirements.patch

diff --git a/queue-5.15/xen-swiotlb-relax-alignment-requirements.patch b/queue-5.15/xen-swiotlb-relax-alignment-requirements.patch
new file mode 100644 (file)
index 0000000..b9aa3f1
--- /dev/null
+++ b/queue-5.15/xen-swiotlb-relax-alignment-requirements.patch
@@ -0,0 +1,78 @@
+From 85fcb57c983f423180ba6ec5d0034242da05cc54 Mon Sep 17 00:00:00 2001
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 10 Feb 2025 08:43:39 +0100
+Subject: xen/swiotlb: relax alignment requirements
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 85fcb57c983f423180ba6ec5d0034242da05cc54 upstream.
+
+When mapping a buffer for DMA via .map_page or .map_sg DMA operations,
+there is no need to check the machine frames to be aligned according
+to the mapped areas size. All what is needed in these cases is that the
+buffer is contiguous at machine level.
+
+So carve out the alignment check from range_straddles_page_boundary()
+and move it to a helper called by xen_swiotlb_alloc_coherent() and
+xen_swiotlb_free_coherent() directly.
+
+Fixes: 9f40ec84a797 ("xen/swiotlb: add alignment check for dma buffers")
+Reported-by: Jan Vejvalka <jan.vejvalka@lfmotol.cuni.cz>
+Tested-by: Jan Vejvalka <jan.vejvalka@lfmotol.cuni.cz>
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Harshvardhan Jha <harshvardhan.j.jha@oracle.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/xen/swiotlb-xen.c |   18 +++++++++++-------
+ 1 file changed, 11 insertions(+), 7 deletions(-)
+
+--- a/drivers/xen/swiotlb-xen.c
++++ b/drivers/xen/swiotlb-xen.c
+@@ -75,19 +75,21 @@ static inline phys_addr_t xen_dma_to_phy
+       return xen_bus_to_phys(dev, dma_to_phys(dev, dma_addr));
+ }
+ 
++static inline bool range_requires_alignment(phys_addr_t p, size_t size)
++{
++      phys_addr_t algn = 1ULL << (get_order(size) + PAGE_SHIFT);
++      phys_addr_t bus_addr = pfn_to_bfn(XEN_PFN_DOWN(p)) << XEN_PAGE_SHIFT;
++
++      return IS_ALIGNED(p, algn) && !IS_ALIGNED(bus_addr, algn);
++}
++
+ static inline int range_straddles_page_boundary(phys_addr_t p, size_t size)
+ {
+       unsigned long next_bfn, xen_pfn = XEN_PFN_DOWN(p);
+       unsigned int i, nr_pages = XEN_PFN_UP(xen_offset_in_page(p) + size);
+-      phys_addr_t algn = 1ULL << (get_order(size) + PAGE_SHIFT);
+ 
+       next_bfn = pfn_to_bfn(xen_pfn);
+ 
+-      /* If buffer is physically aligned, ensure DMA alignment. */
+-      if (IS_ALIGNED(p, algn) &&
+-          !IS_ALIGNED((phys_addr_t)next_bfn << XEN_PAGE_SHIFT, algn))
+-              return 1;
+-
+       for (i = 1; i < nr_pages; i++)
+               if (pfn_to_bfn(++xen_pfn) != ++next_bfn)
+                       return 1;
+@@ -306,7 +308,8 @@ xen_swiotlb_alloc_coherent(struct device
+       phys = dma_to_phys(hwdev, *dma_handle);
+       dev_addr = xen_phys_to_dma(hwdev, phys);
+       if (((dev_addr + size - 1 <= dma_mask)) &&
+-          !range_straddles_page_boundary(phys, size))
++          !range_straddles_page_boundary(phys, size) &&
++          !range_requires_alignment(phys, size))
+               *dma_handle = dev_addr;
+       else {
+               if (xen_create_contiguous_region(phys, order,
+@@ -347,6 +350,7 @@ xen_swiotlb_free_coherent(struct device
+ 
+       if (!WARN_ON((dev_addr + size - 1 > dma_mask) ||
+                    range_straddles_page_boundary(phys, size)) &&
++          !range_requires_alignment(phys, size) &&
+           TestClearPageXenRemapped(page))
+               xen_destroy_contiguous_region(phys, order);
+