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[2a03:2880:30ff:73::face:b00c]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a8d25cecc21sm862212966b.166.2024.09.13.05.28.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 Sep 2024 05:28:01 -0700 (PDT) From: Breno Leitao To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" Cc: corbet@lwn.net, linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)) Subject: [PATCH] x86/bugs: Correct RSB terminology in Kconfig Date: Fri, 13 Sep 2024 05:27:53 -0700 Message-ID: <20240913122754.249306-1-leitao@debian.org> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" RSB stands for "Return Stack Buffer" in industry literature[1]. Update the kernel Kconfig to use this standard term instead of the current "Return-Speculation-Buffer". This change aligns kernel documentation with widely accepted terminology. The line length reduction triggers text reformatting, but no functional text is altered. [1] https://www.intel.com/content/www/us/en/developer/articles/technical/so= ftware-security-guidance/advisory-guidance/return-stack-buffer-underflow.ht= ml Signed-off-by: Breno Leitao Acked-by: Dave Hansen --- arch/x86/Kconfig | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 007bab9f2a0e..5d87d5d7c6d0 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2554,15 +2554,14 @@ config MITIGATION_CALL_DEPTH_TRACKING default y help Compile the kernel with call depth tracking to mitigate the Intel - SKL Return-Speculation-Buffer (RSB) underflow issue. The - mitigation is off by default and needs to be enabled on the - kernel command line via the retbleed=3Dstuff option. For - non-affected systems the overhead of this option is marginal as - the call depth tracking is using run-time generated call thunks - in a compiler generated padding area and call patching. This - increases text size by ~5%. For non affected systems this space - is unused. On affected SKL systems this results in a significant - performance gain over the IBRS mitigation. + SKL Return-Stack-Buffer (RSB) underflow issue. The mitigation is off + by default and needs to be enabled on the kernel command line via the + retbleed=3Dstuff option. For non-affected systems the overhead of this + option is marginal as the call depth tracking is using run-time + generated call thunks in a compiler generated padding area and call + patching. This increases text size by ~5%. For non affected systems + this space is unused. On affected SKL systems this results in a + significant performance gain over the IBRS mitigation. =20 config CALL_THUNKS_DEBUG bool "Enable call thunks and call depth tracking debugging" --=20 2.43.5