| Message ID | 20210422071921.1428607-8-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/7] swiotlb: pass bytes instead of nslabs to swiotlb_init_with_tbl | expand |
On 4/22/21 2:19 AM, Christoph Hellwig wrote: > 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> I tested this patchset and I'm not able to get the override via the command line or via the SEV adjustment function. Looking at the code, swiotlb_default_size is initialized, so the call to swiotlb_adjust_size() always returns without setting the new size. Thanks, Tom > --- > 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); >
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);
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(-)