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Donenfeld" Cc: Andy Lutomirski , Thomas Gleixner , Theodore Ts'o , Nathan Chancellor , Vincenzo Frascino , Nick Desaulniers , Bill Wendling , Justin Stitt , Catalin Marinas , Will Deacon , Mark Rutland , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, llvm@lists.linux.dev References: <20260925-vdso-getrandom-avoid-memset-llvm-24-v2-1-ce640f872393@kernel.org> <179093852073.149722.832232613857480812.b4-ty@kernel.org> Content-Language: fr-FR From: "Christophe Leroy (CS GROUP)" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Le 02/10/2026 à 12:58, Jason A. Donenfeld a écrit : > On Fri, Oct 2, 2026 at 12:57 PM Christophe Leroy (CS GROUP) > wrote: >> >> >> On Fri, 25 Sep 2026 22:46:32 +0100, Nathan Chancellor wrote: >>> After a recent change in LLVM [1], builds with the random vDSO >>> implementation, such as PowerPC and RISC-V, fail when checking the vDSO: >>> >>> arch/powerpc/kernel/vdso/vdso32.so.dbg: dynamic relocations are not supported >>> arch/riscv/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported >>> >>> memset() is now generated when zeroing params->reserved for some builds >>> because LLVM has an optimization (now run in more instances) that can >>> recognize at compile time when it is assigning a static value to a >>> contiguous area of memory and turn that into a call to memset(). Both >>> clang and GCC assume memset() is always available [2]. >>> >>> [...] >> >> Applied, thanks! >> >> [1/1] random: vDSO: Avoid call to memset() when zeroing reserved in __cvdso_getrandom_data() >> (no commit info) > > That's not for you to apply. I'm sending this through my random tree, > along with a handful of other things I need to fix. But I wanted to > let this cook a bit more. I can add your reviewed-by line, though. Sorry I messed up with 'b4 ty', I do not intent to take this patch in my tree.