[ Upstream commit a98959fdbda1849a01b2150bb635ed559ec06700 ]
find_next_iomem_res() finds an iomem resource that covers part of a range
described by "start, end". All callers expect that range to be inclusive,
i.e., both start and end are included, but find_next_iomem_res() doesn't
handle the end address correctly.
If it finds an iomem resource that contains exactly the end address, it
skips it, e.g., if "start, end" is [0x0-0x10000] and there happens to be an
iomem resource [mem 0x10000-0x10000] (the single byte at 0x10000), we skip
it:
find_next_iomem_res(...)
{
start = 0x0;
end = 0x10000;
for (p = next_resource(...)) {
# p->start = 0x10000;
# p->end = 0x10000;
# we *should* return this resource, but this condition is false:
if ((p->end >= start) && (p->start < end))
break;
Adjust find_next_iomem_res() so it allows a resource that includes the
single byte at the end of the range. This is a corner case that we
probably don't see in practice.
Fixes: 58c1b5b07907 ("[PATCH] memory hotadd fixes: find_next_system_ram catch
range fix")
Signed-off-by: Bjorn Helgaas <bhelg...@google.com>
Signed-off-by: Borislav Petkov <b...@suse.de>
CC: Andrew Morton <a...@linux-foundation.org>
CC: Brijesh Singh <brijesh.si...@amd.com>
CC: Dan Williams <dan.j.willi...@intel.com>
CC: H. Peter Anvin <h...@zytor.com>
CC: Lianbo Jiang <liji...@redhat.com>
CC: Takashi Iwai <ti...@suse.de>
CC: Thomas Gleixner <t...@linutronix.de>
CC: Tom Lendacky <thomas.lenda...@amd.com>
CC: Vivek Goyal <vgo...@redhat.com>
CC: Yaowei Bai <baiyao...@cmss.chinamobile.com>
CC: b...@redhat.com
CC: dan.j.willi...@intel.com
CC: dyo...@redhat.com
CC: ke...@lists.infradead.org
CC: mi...@redhat.com
CC: x86-ml <x...@kernel.org>
Link:
http://lkml.kernel.org/r/153805812254.1157.16736368485811773752.st...@bhelgaas-glaptop.roam.corp.google.com
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
kernel/resource.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/resource.c b/kernel/resource.c
index 30e1bc68503b5..155ec873ea4d1 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -319,7 +319,7 @@ int release_resource(struct resource *old)
EXPORT_SYMBOL(release_resource);
/*
- * Finds the lowest iomem resource existing within [res->start.res->end).
+ * Finds the lowest iomem resource existing within [res->start..res->end].
* The caller must specify res->start, res->end, res->flags, and optionally
* desc. If found, returns 0, res is overwritten, if not found, returns -1.
* This function walks the whole tree and not just first level children until
@@ -352,7 +352,7 @@ static int find_next_iomem_res(struct resource *res,
unsigned long desc,
p = NULL;
break;
}
- if ((p->end >= start) && (p->start < end))
+ if ((p->end >= start) && (p->start <= end))
break;
}
--
2.20.1
