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Hibernation: Fix mark_nosave_pages() 

There is a problem in the hibernation code that triggers on some NUMA
systems on which pfn_valid() returns 'true' for some PFNs that don't
belong to any zone.  Namely, there is a BUG_ON() in
memory_bm_find_bit() that triggers for PFNs not belonging to any
zone and passing the pfn_valid() test.  On the affected systems it
triggers when we mark PFNs reported by the platform as not saveable,
because the PFNs in question belong to a region mapped directly using
iorepam() (i.e. the ACPI data area) and they pass the pfn_valid()
test.

Modify memory_bm_find_bit() so that it returns an error if given PFN
doesn't belong to any zone instead of crashing the kernel and ignore
the result returned by it in mark_nosave_pages(), while marking the
"nosave" memory regions.

This doesn't affect the hibernation functionality, as we won't touch
the PFNs in question anyway.

http://bugzilla.kernel.org/show_bug.cgi?id=9966 .

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
hifive-unleashed-5.1
Rafael J. Wysocki 2008-03-12 00:34:57 +01:00 committed by Len Brown
parent baadac8b10
commit a82f7119fd
1 changed files with 34 additions and 7 deletions
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41
kernel/power/snapshot.c
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@ -447,7 +447,7 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
* of @bm->cur_zone_bm are updated.
*/
static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
void **addr, unsigned int *bit_nr)
{
struct zone_bitmap *zone_bm;
@ -461,7 +461,8 @@ static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
zone_bm = zone_bm->next;
BUG_ON(!zone_bm);
if (!zone_bm)
return -EFAULT;
}
bm->cur.zone_bm = zone_bm;
}
@ -479,23 +480,40 @@ static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
pfn -= bb->start_pfn;
*bit_nr = pfn % BM_BITS_PER_CHUNK;
*addr = bb->data + pfn / BM_BITS_PER_CHUNK;
return 0;
}
static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
int error;
memory_bm_find_bit(bm, pfn, &addr, &bit);
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
set_bit(bit, addr);
}
static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
int error;
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
if (!error)
set_bit(bit, addr);
return error;
}
static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
int error;
memory_bm_find_bit(bm, pfn, &addr, &bit);
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
clear_bit(bit, addr);
}
@ -503,8 +521,10 @@ static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
int error;
memory_bm_find_bit(bm, pfn, &addr, &bit);
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
return test_bit(bit, addr);
}
@ -709,8 +729,15 @@ static void mark_nosave_pages(struct memory_bitmap *bm)
region->end_pfn << PAGE_SHIFT);
for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
if (pfn_valid(pfn))
memory_bm_set_bit(bm, pfn);
if (pfn_valid(pfn)) {
/*
* It is safe to ignore the result of
* mem_bm_set_bit_check() here, since we won't
* touch the PFNs for which the error is
* returned anyway.
*/
mem_bm_set_bit_check(bm, pfn);
}
}
}