[PATCH 1/3] powerpc/book3s64/hash/4k: 4k supports only 16TB linear mapping

Aneesh Kumar K.V aneesh.kumar at linux.ibm.com
Wed Sep 18 00:57:00 AEST 2019


With commit: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in the
same 0xc range"), we now split the 64TB address range into 4 contexts each of
16TB. That implies we can do only 16TB linear mapping. Make sure we don't
add physical memory above 16TB if that is present in the system.

Fixes: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in thesame 0xc range")
Reported-by: Cameron Berkenpas <cam at neo-zeon.de>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/mmu.h | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index bb3deb76c951..86cce8189240 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -35,12 +35,16 @@ extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
  * memory requirements with large number of sections.
  * 51 bits is the max physical real address on POWER9
  */
-#if defined(CONFIG_SPARSEMEM_VMEMMAP) && defined(CONFIG_SPARSEMEM_EXTREME) &&  \
-	defined(CONFIG_PPC_64K_PAGES)
+
+#if defined(CONFIG_PPC_64K_PAGES)
+#if defined(CONFIG_SPARSEMEM_VMEMMAP) && defined(CONFIG_SPARSEMEM_EXTREME)
 #define MAX_PHYSMEM_BITS 51
 #else
 #define MAX_PHYSMEM_BITS 46
 #endif
+#else /* CONFIG_PPC_64K_PAGES */
+#define MAX_PHYSMEM_BITS 44
+#endif
 
 /* 64-bit classic hash table MMU */
 #include <asm/book3s/64/mmu-hash.h>
-- 
2.21.0



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