[PATCH AUTOSEL 5.6 190/606] sparc32: use PUD rather than PGD to get PMD in srmmu_nocache_init()

From: Sasha Levin
Date: Mon Jun 08 2020 - 20:30:07 EST


From: Mike Rapoport <rppt@xxxxxxxxxxxxx>

commit c2bc26f7ca1ff1165bb6669a7a4cccc20ffd2ced upstream.

The kbuild test robot reported the following warning:

arch/sparc/mm/srmmu.c: In function 'srmmu_nocache_init': arch/sparc/mm/srmmu.c:300:9: error: variable 'pud' set but not used [-Werror=unused-but-set-variable]
300 | pud_t *pud;

This warning is caused by misprint in the page table traversal in
srmmu_nocache_init() function which accessed a PMD entry using PGD
rather than PUD.

Since sparc32 has only 3 page table levels, the PGD and PUD are
essentially the same and usage of __nocache_fix() removed the type
checking.

Use PUD for the consistency and to silence the compiler warning.

Fixes: 7235db268a2777bc38 ("sparc32: use pgtable-nopud instead of 4level-fixup")
Reported-by: kbuild test robot <lkp@xxxxxxxxx>
Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Anatoly Pugachev <matorola@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20200520132005.GM1059226@xxxxxxxxxxxxx
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/sparc/mm/srmmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index f56c3c9a9793..083ba02c94e6 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -333,7 +333,7 @@ static void __init srmmu_nocache_init(void)
pgd = pgd_offset_k(vaddr);
p4d = p4d_offset(__nocache_fix(pgd), vaddr);
pud = pud_offset(__nocache_fix(p4d), vaddr);
- pmd = pmd_offset(__nocache_fix(pgd), vaddr);
+ pmd = pmd_offset(__nocache_fix(pud), vaddr);
pte = pte_offset_kernel(__nocache_fix(pmd), vaddr);

pteval = ((paddr >> 4) | SRMMU_ET_PTE | SRMMU_PRIV);
--
2.25.1