summaryrefslogtreecommitdiff
path: root/tools
diff options
context:
space:
mode:
authorPawan Gupta <pawan.kumar.gupta@linux.intel.com>2022-03-11 01:02:09 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-04-20 10:34:20 +0300
commitc61d929944c9e9df3cd03b8df9e248fe5962b23e (patch)
tree44426a4cb6e003b4029ec4f574b635e73e963422 /tools
parentaaf27fcaefc15ea51bb2fef550f17c5b71032041 (diff)
downloadlinux-c61d929944c9e9df3cd03b8df9e248fe5962b23e.tar.xz
x86/tsx: Disable TSX development mode at boot
commit 400331f8ffa3bec5c561417e5eec6848464e9160 upstream. A microcode update on some Intel processors causes all TSX transactions to always abort by default[*]. Microcode also added functionality to re-enable TSX for development purposes. With this microcode loaded, if tsx=on was passed on the cmdline, and TSX development mode was already enabled before the kernel boot, it may make the system vulnerable to TSX Asynchronous Abort (TAA). To be on safer side, unconditionally disable TSX development mode during boot. If a viable use case appears, this can be revisited later. [*]: Intel TSX Disable Update for Selected Processors, doc ID: 643557 [ bp: Drop unstable web link, massage heavily. ] Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com> Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/347bd844da3a333a9793c6687d4e4eb3b2419a3e.1646943780.git.pawan.kumar.gupta@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools')
-rw-r--r--tools/arch/x86/include/asm/msr-index.h4
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/arch/x86/include/asm/msr-index.h b/tools/arch/x86/include/asm/msr-index.h
index a7c413432b33..66ae309840fe 100644
--- a/tools/arch/x86/include/asm/msr-index.h
+++ b/tools/arch/x86/include/asm/msr-index.h
@@ -128,9 +128,9 @@
#define TSX_CTRL_RTM_DISABLE BIT(0) /* Disable RTM feature */
#define TSX_CTRL_CPUID_CLEAR BIT(1) /* Disable TSX enumeration */
-/* SRBDS support */
#define MSR_IA32_MCU_OPT_CTRL 0x00000123
-#define RNGDS_MITG_DIS BIT(0)
+#define RNGDS_MITG_DIS BIT(0) /* SRBDS support */
+#define RTM_ALLOW BIT(1) /* TSX development mode */
#define MSR_IA32_SYSENTER_CS 0x00000174
#define MSR_IA32_SYSENTER_ESP 0x00000175