Remove tsx_async_abort kernel parameter since it can be set with the common
clar_cpu_buffers parameter.
Signed-off-by: Daniel Sneddon <daniel.sneddon@xxxxxxxxxxxxxxx>
---
.../admin-guide/kernel-parameters.txt | 41 -------------------
arch/x86/kernel/cpu/bugs.c | 21 ----------
2 files changed, 62 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 2753a1e51da5..961e637b8126 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -6883,47 +6883,6 @@
See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
for more details.
- tsx_async_abort= [X86,INTEL,EARLY] Control mitigation for the TSX Async
- Abort (TAA) vulnerability.
-
- Similar to Micro-architectural Data Sampling (MDS)
- certain CPUs that support Transactional
- Synchronization Extensions (TSX) are vulnerable to an
- exploit against CPU internal buffers which can forward
- information to a disclosure gadget under certain
- conditions.
-
- In vulnerable processors, the speculatively forwarded
- data can be used in a cache side channel attack, to
- access data to which the attacker does not have direct
- access.
-
- This parameter controls the TAA mitigation. The
- options are:
-
- full - Enable TAA mitigation on vulnerable CPUs
- if TSX is enabled.
-
- full,nosmt - Enable TAA mitigation and disable SMT on
- vulnerable CPUs. If TSX is disabled, SMT
- is not disabled because CPU is not
- vulnerable to cross-thread TAA attacks.
- off - Unconditionally disable TAA mitigation
-
- On MDS-affected machines, tsx_async_abort=off can be
- prevented by an active MDS mitigation as both vulnerabilities
- are mitigated with the same mechanism so in order to disable
- this mitigation, you need to specify mds=off too.
-
- Not specifying this option is equivalent to
- tsx_async_abort=full. On CPUs which are MDS affected
- and deploy MDS mitigation, TAA mitigation is not
- required and doesn't provide any additional
- mitigation.
-
- For details see:
- Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
-
turbografx.map[2|3]= [HW,JOY]
TurboGraFX parallel port interface
Format:
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index ed5524bc3ee4..0a09f0d1a343 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -339,27 +339,6 @@ static void __init taa_select_mitigation(void)
cpu_smt_disable(false);
}
-static int __init tsx_async_abort_parse_cmdline(char *str)
-{
- if (!boot_cpu_has_bug(X86_BUG_TAA))
- return 0;
-
- if (!str)
- return -EINVAL;
-
- if (!strcmp(str, "off")) {
- taa_mitigation = TAA_MITIGATION_OFF;
- } else if (!strcmp(str, "full")) {
- taa_mitigation = TAA_MITIGATION_VERW;
- } else if (!strcmp(str, "full,nosmt")) {
- taa_mitigation = TAA_MITIGATION_VERW;
- taa_nosmt = true;
- }
-
- return 0;
-}
-early_param("tsx_async_abort", tsx_async_abort_parse_cmdline);
-
#undef pr_fmt
#define pr_fmt(fmt) "MMIO Stale Data: " fmt
--
2.25.1
