From: Prarit Bhargava prarit@redhat.com
[ 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 prarit@redhat.com Cc: Shuah Khan shuah@kernel.org Cc: Stafford Horne shorne@gmail.com Signed-off-by: Shuah Khan (Samsung OSG) shuah@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 0e6764330241..f9b064ac8d94 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 6437ef39aeea..82adfb33d7a5 100644 --- a/tools/power/cpupower/utils/helpers/amd.c +++ b/tools/power/cpupower/utils/helpers/amd.c @@ -103,6 +103,11 @@ 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;