p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

resource: Include resource end in walk_*() interfaces 

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: 58c1b5b079 ("[PATCH] memory hotadd fixes: find_next_system_ram catch range fix")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/153805812254.1157.16736368485811773752.stgit@bhelgaas-glaptop.roam.corp.google.com
This commit is contained in:
Bjorn Helgaas 2018-09-27 09:22:02 -05:00 committed by Borislav Petkov
parent 51fbf14f25
commit a98959fdbd
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

@ -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;
}