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Tue, 26 May 2026 07:30:18 -0700 (PDT) From: Jiri Olsa X-Google-Original-From: Jiri Olsa Date: Tue, 26 May 2026 16:30:14 +0200 To: Jakub Sitnicki Cc: sashiko-bot@kernel.org, sashiko-reviews@lists.linux.dev, bpf@vger.kernel.org Subject: Re: [PATCHv3 07/12] selftests/bpf: Emit nop,nop10 instructions combo for x86_64 arch Message-ID: References: <20260521124411.31133-8-jolsa@kernel.org> <20260521132121.EEB4E1F000E9@smtp.kernel.org> <87bje277zf.fsf@cloudflare.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87bje277zf.fsf@cloudflare.com> On Tue, May 26, 2026 at 12:58:28PM +0200, Jakub Sitnicki wrote: > On Thu, May 21, 2026 at 01:21 PM GMT, sashiko-bot@kernel.org wrote: > > [...] > > > Would using two consecutive 5-byte nops instead of a single 10-byte > > nop safely provide the padding needed for a 5-byte patch? > > Perhaps worth clarifying that nop5,nop5 wouldn't allow us to leave the > CALL in nop10 tail after the optimize/unoptimize cycle. right, also we need to have single instruction for that to have some assurance the app won't jump in the middle jirka