From: Benjamin Herrenschmidt Date: Fri, 23 Sep 2005 20:24:07 +0000 (-0700) Subject: [PATCH] ppc64: Fix huge pages MMU mapping bug X-Git-Tag: v2.6.14-rc3~51^2~11 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=67b108131df1230bad20a7279a8897de123d690b;p=linux-2.6-omap-h63xx.git [PATCH] ppc64: Fix huge pages MMU mapping bug Current kernel has a couple of sneaky bugs in the ppc64 hugetlb code that cause huge pages to be potentially left stale in the hash table and TLBs (improperly invalidated), with all the nasty consequences that can have. One is that we forgot to set the "secondary" bit in the hash PTEs when hashing a huge page in the secondary bucket (fortunately very rare). The other one is on non-LPAR machines (like Apple G5s), flush_hash_range() which is used to flush a batch of PTEs simply did not work for huge pages. Historically, our huge page code didn't batch, but this was changed without fixing this routine. This patch fixes both. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/ppc64/mm/hash_native.c b/arch/ppc64/mm/hash_native.c index 7626bb59954..eb1bbb5b6c1 100644 --- a/arch/ppc64/mm/hash_native.c +++ b/arch/ppc64/mm/hash_native.c @@ -343,9 +343,7 @@ static void native_flush_hash_range(unsigned long context, hpte_t *hptep; unsigned long hpte_v; struct ppc64_tlb_batch *batch = &__get_cpu_var(ppc64_tlb_batch); - - /* XXX fix for large ptes */ - unsigned long large = 0; + unsigned long large; local_irq_save(flags); @@ -358,6 +356,7 @@ static void native_flush_hash_range(unsigned long context, va = (vsid << 28) | (batch->addr[i] & 0x0fffffff); batch->vaddr[j] = va; + large = pte_huge(batch->pte[i]); if (large) vpn = va >> HPAGE_SHIFT; else diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c index 338771ec70d..0ea0994ed97 100644 --- a/arch/ppc64/mm/hugetlbpage.c +++ b/arch/ppc64/mm/hugetlbpage.c @@ -710,10 +710,13 @@ repeat: hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL; slot = ppc_md.hpte_insert(hpte_group, va, prpn, - HPTE_V_LARGE, rflags); + HPTE_V_LARGE | + HPTE_V_SECONDARY, + rflags); if (slot == -1) { if (mftb() & 0x1) - hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL; + hpte_group = ((hash & htab_hash_mask) * + HPTES_PER_GROUP)&~0x7UL; ppc_md.hpte_remove(hpte_group); goto repeat;