Hi, This is shifting up, IMO:
+ microcode <<= 32; /* shift them down */ Thanks, Anton > -----Original Message----- > From: Brian Inglis <[email protected]> > Sent: Tuesday, July 07, 2020 1:34 PM > To: [email protected] > Subject: [PATCH] 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 f1bc1c7405..f637dfd8e4 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; > -- > 2.27.0
