[PATCH 7/7] swiotlb: don't override the command line in swiotlb_adjust_size
From: Christoph Hellwig <hch@lst.de>
Date: 2021-04-22 07:22:22
Also in:
linux-iommu, linux-mips, xen-devel
Subsystem:
dma mapping helpers, the rest · Maintainers:
Marek Szyprowski, Linus Torvalds
When the user specified an explicit swiotlb size on the command line,
the achitecture code should not override it.
Fixes: 2cbc2776efe4 ("swiotlb: remove swiotlb_nr_tbl")
Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
kernel/dma/swiotlb.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 87d06ddf4753f3..aef02a3825b494 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c@@ -106,7 +106,9 @@ void swiotlb_set_max_segment(unsigned int val) unsigned long swiotlb_size_or_default(void) { - return swiotlb_default_size; + if (swiotlb_default_size) + return swiotlb_default_size; + return IO_TLB_DEFAULT_SIZE; } void __init swiotlb_adjust_size(unsigned long size)
@@ -116,6 +118,8 @@ void __init swiotlb_adjust_size(unsigned long size) * architectures such as those supporting memory encryption to * adjust/expand SWIOTLB size for their use. */ + if (swiotlb_default_size) + return; swiotlb_default_size = ALIGN(size, IO_TLB_SEGSIZE << IO_TLB_SHIFT); pr_info("SWIOTLB bounce buffer size adjusted to %luMB", swiotlb_default_size >> 20);
--
2.30.1