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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-490417aeaecsm1419675e9.4.2026.05.21.11.03.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 May 2026 11:03:38 -0700 (PDT) Date: Thu, 21 May 2026 19:03:36 +0100 From: David Laight To: Andreas Schwab Cc: Marco Elver , Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Subject: Re: [PATCH] m68k: Implement _THIS_IP_ using inline asm Message-ID: <20260521190336.44dc3882@pumpkin> In-Reply-To: <87h5o0zteu.fsf@igel.home> References: <20260521123438.147789-1-elver@google.com> <87h5o0zteu.fsf@igel.home> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 21 May 2026 17:14:33 +0200 Andreas Schwab wrote: > On Mai 21 2026, Marco Elver wrote: > > > version. Additionally, avoiding taking the address of a label prevents > > compilers from emitting spurious indirect branch targets (e.g. ENDBR or > > BTI) under control-flow integrity schemes. > > Ignoring the fact that m68k will never gain such a feature, dot is still > a label. But it wont be one the compiler sees. I think it is an assembler variable that is automatically updated, so not actually a label that ends up in the symbol table. Even the '1b:' in some of the other examples are only second class labels. -- David > If you want to avoid a label, you need to use %pc(0) (or > %pc(-2) for an address at insn boundary). >