From 54bb6589c31e211e9443c3f1a80b9d07409ed7a4 Mon Sep 17 00:00:00 2001 From: Brian Inglis Date: Tue, 7 Jul 2020 13:00:36 -0600 Subject: [PATCH] fhandler_proc.cc(format_proc_cpuinfo): add microcode registry lookup values Re: CPU microcode reported wrong in /proc/cpuinfo https://sourceware.org/pipermail/cygwin/2020-May/245063.html earlier Windows releases used different registry values to store microcode revisions depending on the MSR name being used to get microcode revisions: add these alternative registry values to the cpuinfo registry value lookup; iterate thru the registry data until a valid microcode revision is found; some revision values are in the high bits, so if the low bits are all clear, shift the revision value down into the low bits --- winsup/cygwin/fhandler_proc.cc | 44 +++++++++++++++++++++++++++------- 1 file changed, 35 insertions(+), 9 deletions(-) diff --git a/winsup/cygwin/fhandler_proc.cc b/winsup/cygwin/fhandler_proc.cc index f1bc1c740..f637dfd8e 100644 --- a/winsup/cygwin/fhandler_proc.cc +++ b/winsup/cygwin/fhandler_proc.cc @@ -692,26 +692,52 @@ format_proc_cpuinfo (void *, char *&destbuf) union { LONG uc_len; /* -max size of buffer before call */ - char uc_microcode[16]; - } uc; + char uc_microcode[16]; /* at least 8 bytes */ + } uc[4]; /* microcode values changed historically */ - RTL_QUERY_REGISTRY_TABLE tab[3] = + RTL_QUERY_REGISTRY_TABLE tab[6] = { { NULL, RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_NOSTRING, - L"~Mhz", &cpu_mhz, REG_NONE, NULL, 0 }, + L"~Mhz", &cpu_mhz, REG_NONE, NULL, 0 }, { NULL, RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_NOSTRING, - L"Update Revision", &uc, REG_NONE, NULL, 0 }, + L"Update Revision", &uc[0], REG_NONE, NULL, 0 }, + /* latest MSR */ + { NULL, RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_NOSTRING, + L"Update Signature", &uc[1], REG_NONE, NULL, 0 }, + /* previous MSR */ + { NULL, RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_NOSTRING, + L"CurrentPatchLevel", &uc[2], REG_NONE, NULL, 0 }, + /* earlier MSR */ + { NULL, RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_NOSTRING, + L"Platform Specific Field1", &uc[3], REG_NONE, NULL, 0 }, + /* alternative */ { NULL, 0, NULL, NULL, 0, NULL, 0 } }; - memset (&uc, 0, sizeof (uc.uc_microcode)); - uc.uc_len = -16; /* -max size of microcode buffer */ + for (size_t uci = 0; uci < sizeof (uc)/sizeof (*uc); ++uci) + { + memset (&uc[uci], 0, sizeof (uc[uci])); + uc[uci].uc_len = -(LONG)sizeof (uc[0].uc_microcode); + /* neg buffer size */ + } + RtlQueryRegistryValues (RTL_REGISTRY_ABSOLUTE, cpu_key, tab, NULL, NULL); cpu_mhz = ((cpu_mhz - 1) / 10 + 1) * 10; /* round up to multiple of 10 */ DWORD bogomips = cpu_mhz * 2; /* bogomips is double cpu MHz since MMX */ - long long microcode = 0; /* at least 8 bytes for AMD */ - memcpy (µcode, &uc, sizeof (microcode)); + + unsigned long long microcode = 0; /* needs 8 bytes */ + for (size_t uci = 0; uci < sizeof (uc)/sizeof (*uc) && !microcode; ++uci) + { + /* still neg buffer size => no data */ + if (-(LONG)sizeof (uc[uci].uc_microcode) != uc[uci].uc_len) + { + memcpy (µcode, uc[uci].uc_microcode, sizeof (microcode)); + + if (!(microcode & 0xFFFFFFFFLL)) /* some values in high bits */ + microcode <<= 32; /* shift them down */ + } + } bufptr += __small_sprintf (bufptr, "processor\t: %d\n", cpu_number); uint32_t maxf, vendor_id[4], unused;