AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

xen/swiotlb: Use page alignment for early buffer allocation.

Browse Source 
This fixes an odd bug found on a Dell PowerEdge 1850/0RC130
(BIOS A05 01/09/2006) where all of the modules doing pci_set_dma_mask
would fail with:

ata_piix 0000:00:1f.1: enabling device (0005 -> 0007)
ata_piix 0000:00:1f.1: can't derive routing for PCI INT A
ata_piix 0000:00:1f.1: BMDMA: failed to set dma mask, falling back to PIO

The issue was the Xen-SWIOTLB was allocated such as that the end of
buffer was stradling a page (and also above 4GB). The fix was
spotted by Kalev Leonid  which was to piggyback on git commit
e79f86b2ef "swiotlb: Use page alignment
for early buffer allocation" which:

	We could call free_bootmem_late() if swiotlb is not used, and
	it will shrink to page alignment.

	So alloc them with page alignment at first, to avoid lose two pages

And doing that fixes the outstanding issue.

CC: stable@kernel.org
Suggested-by: "Kalev, Leonid" <Leonid.Kalev@ca.com>
Reported-and-Tested-by: "Taylor, Neal E" <Neal.Taylor@ca.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk 2011-12-15 11:28:46 -05:00
parent d3db728125
commit 63a741757d
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/xen/swiotlb-xen.c
View File

@ -166,7 +166,7 @@ void __init xen_swiotlb_init(int verbose)
/*
* Get IO TLB memory from any location.
*/
xen_io_tlb_start = alloc_bootmem(bytes);
xen_io_tlb_start = alloc_bootmem_pages(PAGE_ALIGN(bytes));
if (!xen_io_tlb_start) {
m = "Cannot allocate Xen-SWIOTLB buffer!\n";
goto error;
@ -179,7 +179,7 @@ void __init xen_swiotlb_init(int verbose)
bytes,
xen_io_tlb_nslabs);
if (rc) {
free_bootmem(__pa(xen_io_tlb_start), bytes);
free_bootmem(__pa(xen_io_tlb_start), PAGE_ALIGN(bytes));
m = "Failed to get contiguous memory for DMA from Xen!\n"\
"You either: don't have the permissions, do not have"\
" enough free memory under 4GB, or the hypervisor memory"\