From 588974857359861891f478a070b1dc7ae04a3880 Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Wed, 31 May 2017 11:25:20 -0400 Subject: [PATCH] sparc64: reset mm cpumask after wrap After a wrap (getting a new context version) a process must get a new context id, which means that we would need to flush the context id from the TLB before running for the first time with this ID on every CPU. But, we use mm_cpumask to determine if this process has been running on this CPU before, and this mask is not reset after a wrap. So, there are two possible fixes for this issue: 1. Clear mm cpumask whenever mm gets a new context id 2. Unconditionally flush context every time process is running on a CPU This patch implements the first solution Signed-off-by: Pavel Tatashin Reviewed-by: Bob Picco Reviewed-by: Steven Sistare Signed-off-by: David S. Miller --- arch/sparc/mm/init_64.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 7ca1b9dc7d64..f8e30a3906be 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -759,6 +759,8 @@ void get_new_mmu_context(struct mm_struct *mm) goto out; } } + if (mm->context.sparc64_ctx_val) + cpumask_clear(mm_cpumask(mm)); mmu_context_bmap[new_ctx>>6] |= (1UL << (new_ctx & 63)); new_ctx |= (tlb_context_cache & CTX_VERSION_MASK); out: