From 47f03c780e1222aaade358307f1b4fa8815ec1f9 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Mon, 8 Oct 2018 11:06:19 -0400 Subject: [PATCH] cpupower: Fix coredump on VMWare [ Upstream commit f69ffc5d3db8f1f03fd6d1df5930f9a1fbd787b6 ] cpupower crashes on VMWare guests. The guests have the AMD PStateDef MSR (0xC0010064 + state number) set to zero. As a result fid and did are zero and the crash occurs because of a divide by zero (cof = fid/did). This can be prevented by checking the enable bit in the PStateDef MSR before calculating cof. By doing this the value of pstate[i] remains zero and the value can be tested before displaying the active Pstates. Check the enable bit in the PstateDef register for all supported families and only print out enabled Pstates. Signed-off-by: Prarit Bhargava Cc: Shuah Khan Cc: Stafford Horne Signed-off-by: Shuah Khan (Samsung OSG) Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- tools/power/cpupower/utils/cpufreq-info.c | 2 ++ tools/power/cpupower/utils/helpers/amd.c | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/tools/power/cpupower/utils/cpufreq-info.c b/tools/power/cpupower/utils/cpufreq-info.c index df43cd4..ccd08dd 100644 --- a/tools/power/cpupower/utils/cpufreq-info.c +++ b/tools/power/cpupower/utils/cpufreq-info.c @@ -200,6 +200,8 @@ static int get_boost_mode(unsigned int cpu) printf(_(" Boost States: %d\n"), b_states); printf(_(" Total States: %d\n"), pstate_no); for (i = 0; i < pstate_no; i++) { + if (!pstates[i]) + continue; if (i < b_states) printf(_(" Pstate-Pb%d: %luMHz (boost state)" "\n"), i, pstates[i]); diff --git a/tools/power/cpupower/utils/helpers/amd.c b/tools/power/cpupower/utils/helpers/amd.c index bb41cdd..58d2399 100644 --- a/tools/power/cpupower/utils/helpers/amd.c +++ b/tools/power/cpupower/utils/helpers/amd.c @@ -119,6 +119,11 @@ int decode_pstates(unsigned int cpu, unsigned int cpu_family, } if (read_msr(cpu, MSR_AMD_PSTATE + i, &pstate.val)) return -1; + if ((cpu_family == 0x17) && (!pstate.fam17h_bits.en)) + continue; + else if (!pstate.bits.en) + continue; + pstates[i] = get_cof(cpu_family, pstate); } *no = i; -- 2.7.4