From 5fea39ace311723dab53460ae7b51b80746e0d3f Mon Sep 17 00:00:00 2001 From: Leonid Shatz Date: Wed, 31 Dec 2014 19:07:44 +0100 Subject: [PATCH] gallium/util: make sure cache line size is not zero The "normal" detection (querying clflush size) already made sure it is non-zero, however another method did not. This lead to crashes if this value happened to be zero (apparently can happen in virtualized environments at least). This fixes https://bugs.freedesktop.org/show_bug.cgi?id=87913 Cc: "10.4" --- src/gallium/auxiliary/util/u_cpu_detect.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/gallium/auxiliary/util/u_cpu_detect.c b/src/gallium/auxiliary/util/u_cpu_detect.c index 28197f4a9d8..23ab46c54bc 100644 --- a/src/gallium/auxiliary/util/u_cpu_detect.c +++ b/src/gallium/auxiliary/util/u_cpu_detect.c @@ -409,8 +409,12 @@ util_cpu_detect(void) } if (regs[0] >= 0x80000006) { + /* should we really do this if the clflush size above worked? */ + unsigned int cacheline; cpuid(0x80000006, regs2); - util_cpu_caps.cacheline = regs2[2] & 0xFF; + cacheline = regs2[2] & 0xFF; + if (cacheline > 0) + util_cpu_caps.cacheline = cacheline; } if (!util_cpu_caps.has_sse) {