From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2a07:de40:b251:101:10:150:64:1]) by sourceware.org (Postfix) with ESMTPS id 917E63858C2C for ; Tue, 13 Feb 2024 12:12:49 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 917E63858C2C Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 917E63858C2C Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2a07:de40:b251:101:10:150:64:1 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1707826371; cv=none; b=ILFkIHsJ4+TbIDulzP7PCZnsFzyeEBZ1VaEezleSC9BtNICvqi9Ul3J5UAkQeq47SNGAaGdXlNT2NouGDvRgQJZMkPHxcAHHZXNqtmFEAENpOWp4jfdJBz1V3TY9thA6y+CsTrF63X9G4XKZfH9RuuxuQgafwa3ZZAspnQ8AIJo= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1707826371; c=relaxed/simple; bh=0f0U8JgGcy7CBGdvDMbDzieTLpmwtQJDUYdd3tGSVrI=; h=DKIM-Signature:DKIM-Signature:DKIM-Signature:DKIM-Signature:From: To:Subject:Date:Message-ID:MIME-Version; b=Y8cgIDu86X7URj5PVoKJWtC00sdDisqq4kSL0bn/QmP4cZ+P1uRQT9RSk3yDn7zaMeiXzApNFyKaHhHXHgZLbNFgkafG2Ek6GjuwLpesmkKoZUkqZKajaurUvj7W1m4EtKHmq+SpxqnfCskOsPnE663LjFm4gSWSG4krn/9dS5w= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from hawking.nue2.suse.org (unknown [10.168.4.11]) by smtp-out1.suse.de (Postfix) with ESMTP id AC86D21F74; Tue, 13 Feb 2024 12:12:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1707826368; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8rrAToq23156XXS+PVSILTdJk6w5MMXLxABgdmRJWXM=; b=aijHc6umTwRUBTxKKeX9pVpO3i646i1aipPbdoOZ/tQzKj59Q1n0j0Sv5r2hJWpzsTPEDh 0ZOYqwIUb+SUAKO8/KczsitMJXro5cV5GbTS4ZjcwVBaVrALH6mMVeZ/Ov/5tKaueZwEzW poMtDBBlFxErozV83/97VpaQnOOuFKk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1707826368; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8rrAToq23156XXS+PVSILTdJk6w5MMXLxABgdmRJWXM=; b=7i/M7R25BUh/cQ5Tfb1cRFmw+p7T++ZaX4LnduvxMK4JKbFLXXtoT3yY0/sU30Wys+u8q7 behZiXD+wjqvsCBA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1707826368; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8rrAToq23156XXS+PVSILTdJk6w5MMXLxABgdmRJWXM=; b=aijHc6umTwRUBTxKKeX9pVpO3i646i1aipPbdoOZ/tQzKj59Q1n0j0Sv5r2hJWpzsTPEDh 0ZOYqwIUb+SUAKO8/KczsitMJXro5cV5GbTS4ZjcwVBaVrALH6mMVeZ/Ov/5tKaueZwEzW poMtDBBlFxErozV83/97VpaQnOOuFKk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1707826368; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8rrAToq23156XXS+PVSILTdJk6w5MMXLxABgdmRJWXM=; b=7i/M7R25BUh/cQ5Tfb1cRFmw+p7T++ZaX4LnduvxMK4JKbFLXXtoT3yY0/sU30Wys+u8q7 behZiXD+wjqvsCBA== Received: by hawking.nue2.suse.org (Postfix, from userid 17005) id 99C364A03A6; Tue, 13 Feb 2024 13:12:48 +0100 (CET) From: Andreas Schwab To: Florian Weimer Cc: Simon Chopin , libc-alpha@sourceware.org Subject: Re: [PATCH] Linux: Switch back to assembly syscall wrapper for prctl (bug 29770) In-Reply-To: <87jzn8inp6.fsf@oldenburg.str.redhat.com> (Florian Weimer's message of "Tue, 13 Feb 2024 12:54:45 +0100") References: <87mssir1u6.fsf@oldenburg.str.redhat.com> <87jzn8inp6.fsf@oldenburg.str.redhat.com> X-Yow: WHY are we missing KOJAK? Date: Tue, 13 Feb 2024 13:12:48 +0100 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Authentication-Results: smtp-out1.suse.de; none X-Spam-Level: X-Spam-Score: 0.20 X-Spamd-Result: default: False [0.20 / 50.00]; TO_DN_SOME(0.00)[]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; BAYES_HAM(-0.42)[78.13%]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; NEURAL_SPAM_SHORT(1.71)[0.571]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:email]; FUZZY_BLOCKED(0.00)[rspamd.com] X-Spam-Status: No, score=-3.2 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Feb 13 2024, Florian Weimer wrote: > “ > Commit ff026950e280bc3e9487b41b460fb31bc5b57721 ("Add a C wrapper for > prctl [BZ #25896]") replaced the assembler wrapper with a C function. > However, on powerpc64le-linux-gnu, the C variadic function > implementation requires extra work in the caller to set up the parameter > save area. Calling a function that needs a parameter save area without > one (because the prototype used indicates the function is not variadic) > corrupts the caller's stack. Switch back to the assembler > implementation on most targets and only keep the C implementation for > x86-64 x32. > ” That does not explain why the compiler did not set up the parameter save area even though the declaration in is varadic. Do I understand correctly that some software uses a private declaration that is prototyped but non-variadic? -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."