From 4ecc804d54ad1f6e9c64f7379cb24b319a9f3f2b Mon Sep 17 00:00:00 2001 From: Brian Inglis Date: Mon, 3 Aug 2020 10:22:46 -0600 Subject: [PATCH] fhandler_proc.cc(format_proc_cpuinfo): add SERIALIZE instruction flag CPUID 7:0 EDX[14] serialize added in linux-next 5.8 by Ricardo Neri-Calderon: The Intel architecture defines a set of Serializing Instructions (a detailed definition can be found in Vol.3 Section 8.3 of the Intel "main" manual, SDM). However, these instructions do more than what is required, have side effects and/or may be rather invasive. Furthermore, some of these instructions are only available in kernel mode or may cause VMExits. Thus, software using these instructions only to serialize execution (as defined in the manual) must handle the undesired side effects. As indicated in the name, SERIALIZE is a new Intel architecture Serializing Instruction. Crucially, it does not have any of the mentioned side effects. Also, it does not cause VMExit and can be used in user mode. This new instruction is currently documented in the latest "extensions" manual (ISE). It will appear in the "main" manual in the future. https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/arch/x86/include/asm/cpufeatures.h?id=85b23fbc7d88f8c6e3951721802d7845bc39663d --- winsup/cygwin/fhandler_proc.cc | 1 + 1 file changed, 1 insertion(+) diff --git a/winsup/cygwin/fhandler_proc.cc b/winsup/cygwin/fhandler_proc.cc index 4bb8bea17..72ffa89cd 100644 --- a/winsup/cygwin/fhandler_proc.cc +++ b/winsup/cygwin/fhandler_proc.cc @@ -1578,6 +1578,7 @@ format_proc_cpuinfo (void *, char *&destbuf) ftcprint (features1, 4, "fsrm"); /* fast short REP MOVSB */ ftcprint (features1, 8, "avx512_vp2intersect"); /* vec intcpt d/q */ ftcprint (features1, 10, "md_clear"); /* verw clear buf */ + ftcprint (features1, 14, "serialize"); /* SERIALIZE instruction */ ftcprint (features1, 18, "pconfig"); /* platform config */ ftcprint (features1, 19, "arch_lbr"); /* last branch records */ ftcprint (features1, 28, "flush_l1d"); /* flush l1d cache */