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McKenney" , Kernel Hardening , Greg Kroah-Hartman , Masahiro Yamada , Linux Kbuild mailing list , LKML , clang-built-linux , linux-pci@vger.kernel.org, Will Deacon , Linux ARM 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 Wed, Jun 24, 2020 at 2:52 PM Sami Tolvanen wrote: > > On Wed, Jun 24, 2020 at 01:58:57PM -0700, 'Nick Desaulniers' via Clang Built Linux wrote: > > On Wed, Jun 24, 2020 at 1:33 PM Sami Tolvanen wrote: > > > > > > Filter out CC_FLAGS_LTO for the vDSO. > > > > Just curious about this patch (and the following one for x86's vdso), > > do you happen to recall specifically what the issues with the vdso's > > are? > > I recall the compiler optimizing away functions at some point, but as > LTO is not really needed in the vDSO, it's just easiest to disable it > there. Sounds fishy; with extern linkage then I would think it's not safe to eliminate functions. Probably unnecessary for the initial implementation, and something we can follow up on, but always good to have an answer to the inevitable question "why?" in the commit message. -- Thanks, ~Nick Desaulniers _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel