4.9-stable review patch. If anyone has any objections, please let me know.
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From: Alexey Brodkin abrodkin@synopsys.com
commit 6e3761145a9ba3ce267c330b6bff51cf6a057b06 upstream.
swap was broken on ARC due to silly copy-paste issue.
We encode offset from swapcache page in __swp_entry() as (off << 13) but were not decoding back in __swp_offset() as (off >> 13) - it was still (off << 13).
This finally fixes swap usage on ARC.
| # mkswap /dev/sda2 | | # swapon -a -e /dev/sda2 | Adding 500728k swap on /dev/sda2. Priority:-2 extents:1 across:500728k | | # free | total used free shared buffers cached | Mem: 765104 13456 751648 4736 8 4736 | -/+ buffers/cache: 8712 756392 | Swap: 500728 0 500728
Cc: stable@vger.kernel.org Signed-off-by: Alexey Brodkin abrodkin@synopsys.com Signed-off-by: Vineet Gupta vgupta@synopsys.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arc/include/asm/pgtable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -378,7 +378,7 @@ void update_mmu_cache(struct vm_area_str
/* Decode a PTE containing swap "identifier "into constituents */ #define __swp_type(pte_lookalike) (((pte_lookalike).val) & 0x1f) -#define __swp_offset(pte_lookalike) ((pte_lookalike).val << 13) +#define __swp_offset(pte_lookalike) ((pte_lookalike).val >> 13)
/* NOPs, to keep generic kernel happy */ #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })