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Hallyn" , Kees Cook , Arnd Bergmann , Nathan Chancellor , linux-arm-kernel@lists.infradead.org, ndesaulniers@google.com, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, David Laight , James Morse , Andrew Morton , Andreas =?iso-8859-1?Q?F=E4rber?= , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Feb 19, 2021 at 03:08:13PM -0800, Jian Cai wrote: > diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening > index 269967c4fc1b..146b75a79d9e 100644 > --- a/security/Kconfig.hardening > +++ b/security/Kconfig.hardening > @@ -121,6 +121,16 @@ choice > > endchoice > > +config HARDEN_SLS_ALL > + bool "enable SLS vulnerability hardening" > + default n Please get rid of this useless "default n" > + depends on $(cc-option,-mharden-sls=all) > + help > + Enables straight-line speculation vulnerability hardening on ARM and ARM64 > + architectures. It inserts speculation barrier sequences (SB or DSB+ISB > + depending on the target architecture) after RET and BR, and replacing > + BLR with BL+BR sequence. Given that this is in an architecture independent Kconfig file, and it detects support in CC for this feature, why should this help text be written to be specific to a couple of architectures? Will this feature only ever be available on these two architectures? What if someone adds support for another architecture? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel