diff options
| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2022-03-10 14:02:09 -0800 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-04-11 09:58:40 +0200 |
| commit | 400331f8ffa3bec5c561417e5eec6848464e9160 (patch) | |
| tree | a13d7ac52030156c867f812614e3ccf75b5c6ea5 /arch/x86/include/asm | |
| parent | 258f3b8c3210b03386e4ad92b4bd8652b5c1beb3 (diff) | |
x86/tsx: Disable TSX development mode at boot
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
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/msr-index.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 0eb90d21049e..ee15311b6be1 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/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 |