[PATCH 4.19 055/195] powerpc/pseries: Advance pfn if section is not present in lmb_is_removable()

From: Greg Kroah-Hartman
Date: Mon Feb 10 2020 - 08:35:23 EST


From: Pingfan Liu <kernelfans@xxxxxxxxx>

commit fbee6ba2dca30d302efe6bddb3a886f5e964a257 upstream.

In lmb_is_removable(), if a section is not present, it should continue
to test the rest of the sections in the block. But the current code
fails to do so.

Fixes: 51925fb3c5c9 ("powerpc/pseries: Implement memory hotplug remove in the kernel")
Cc: stable@xxxxxxxxxxxxxxx # v4.1+
Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1578632042-12415-1-git-send-email-kernelfans@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/powerpc/platforms/pseries/hotplug-memory.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -366,8 +366,10 @@ static bool lmb_is_removable(struct drme

for (i = 0; i < scns_per_block; i++) {
pfn = PFN_DOWN(phys_addr);
- if (!pfn_present(pfn))
+ if (!pfn_present(pfn)) {
+ phys_addr += MIN_MEMORY_BLOCK_SIZE;
continue;
+ }

rc &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
phys_addr += MIN_MEMORY_BLOCK_SIZE;