Thread (3 messages) 3 messages, 2 authors, 2017-07-25

Re: [PATCH] powerpc/mm: Disable registering 16G hugepage size for powernv platform

From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2017-07-24 10:28:14

"Aneesh Kumar K.V" [off-list ref] writes:
We don't support allocating them runtime. Only supported mechanism as of now is
HMC based hypervisor interface. So disable 16G hugetlb on powernv platform

Signed-off-by: Aneesh Kumar K.V <redacted>
---

May be this should go to -stable ?. To show the 16G pagesize in
/sys/kernel/mm/hugepages/ confuse users
It's a bit of a hack :/

16G also shows up on pseries, when there are no pages pre-allocated,
which is also confusing.

Ideally we'd only show sizes that can be allocated at runtime, OR were
preallocated, regardless of platform.

Is there an easy way to do that?

cheers
quoted hunk ↗ jump to hunk
 arch/powerpc/mm/hugetlbpage.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index e1bf5ca397fe..28ea94da0707 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -24,6 +24,7 @@
 #include <asm/tlb.h>
 #include <asm/setup.h>
 #include <asm/hugetlb.h>
+#include <asm/machdep.h>
 
 #ifdef CONFIG_HUGETLB_PAGE
 
@@ -749,7 +750,8 @@ static int __init add_huge_page_size(unsigned long long size)
 				return -EINVAL;
 		}
 	} else {
-		if (mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G)
+		if ((mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G)
+		    || (mmu_psize == MMU_PAGE_16G && machine_is(powernv)))
 			return -EINVAL;
 	}
 #endif
-- 
2.7.4
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help