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[59.102.73.37]) by smtp.gmail.com with ESMTPSA id g8sm1425288pfo.85.2021.06.04.03.06.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Jun 2021 03:06:17 -0700 (PDT) Date: Fri, 4 Jun 2021 20:06:14 +1000 From: Balbir Singh To: Kees Cook Cc: Thomas Gleixner , "mingo@redhat.com" , "linux-kernel@vger.kernel.org" , "peterz@infradead.org" , "torvalds@linux-foundation.org" , "jpoimboe@redhat.com" , "x86@kernel.org" , "tony.luck@intel.com" , "dave.hansen@intel.com" , "thomas.lendacky@amd.com" , "benh@kernel.crashing.org" , linux-hardening@vger.kernel.org Subject: Re: [PATCH v4 0/5] Next revision of the L1D flush patches Message-ID: References: <20210108121056.21940-1-sblbir@amazon.com> <202104081319.DAB1D817@keescook> <87y2d5tpjh.ffs@nanos.tec.linutronix.de> <87tunsofan.ffs@nanos.tec.linutronix.de> <202104281307.F9FCF660@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202104281307.F9FCF660@keescook> Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Wed, Apr 28, 2021 at 01:08:05PM -0700, Kees Cook wrote: > On Tue, Apr 27, 2021 at 12:24:16AM +0200, Thomas Gleixner wrote: > > On Mon, Apr 26 2021 at 10:31, Thomas Gleixner wrote: > > > On Thu, Apr 08 2021 at 13:23, Kees Cook wrote: > > >> > > >> I'd still really like to see this -- it's a big hammer, but that's the > > >> point for cases where some new flaw appears and we can point to the > > >> toolbox and say "you can mitigate it with this while you wait for new > > >> kernel/CPU." > > >> > > >> Any further thoughts from x86 maintainers? This seems like it addressed > > >> all of tglx's review comments. > > > > > > Sorry for dropping the ball on this. It's in my list of things to deal > > > with. Starting to look at it now. > > > > So I went through the pile and for remorse I sat down and made the > > tweaks I think are necessary myself. > > > > I've pushed out the result to > > > > git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/l1dflush > > Oh excellent; thank you for doing this! > Thanks again Thomas! I no longer have access to the bare metal hardware, but I was able to test this under qemu with some emulation changes. The changes worked as expected. Folks on the list/cc, appreciate any tested-by or additional reviewed-by tags if you do happen to review/test. Thanks, Balbir Singh.