iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

kernel/resource: Increment by align value in get_free_mem_region()

Browse Source 
[ Upstream commit 659aa050a53817157b7459529538598a6449c1d3 ]

Currently get_free_mem_region() searches for available capacity
in increments equal to the region size being requested. This can
cause the search to take giant steps through the resource leaving
needless gaps and missing available space.

Specifically 'cxl create-region' fails with ERANGE even though capacity
of the given size and CXL's expected 256M x InterleaveWays alignment can
be satisfied.

Replace the total-request-size increment with a next alignment increment
so that the next possible address is always examined for availability.

Fixes: 14b80582c43e ("resource: Introduce alloc_free_mem_region()")
Reported-by: Dmytro Adamenko <dmytro.adamenko@intel.com>
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20231113221324.1118092-1-alison.schofield@intel.com
Cc: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Alison Schofield 2023-11-13 14:13:24 -08:00 committed by Greg Kroah-Hartman
parent 4c269350e3
commit e4a5b2f60e
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/resource.c
View File

@ -1847,8 +1847,8 @@ get_free_mem_region(struct device *dev, struct resource *base,
write_lock(&resource_lock);
for (addr = gfr_start(base, size, align, flags);
gfr_continue(base, addr, size, flags);
addr = gfr_next(addr, size, flags)) {
gfr_continue(base, addr, align, flags);
addr = gfr_next(addr, align, flags)) {
if (__region_intersects(base, addr, size, 0, IORES_DESC_NONE) !=
REGION_DISJOINT)
continue;