From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=LaeB=D4=redhat.com=fweimer@sourceware.org>
Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124])
	by sourceware.org (Postfix) with ESMTPS id 5B9A53858D20
	for <libc-alpha@sourceware.org>; Fri, 11 Aug 2023 10:17:23 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 5B9A53858D20
Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com
Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;
	s=mimecast20190719; t=1691749042;
	h=from:from:reply-to:subject:subject:date:date:message-id:message-id:
	 to:to:cc:cc:mime-version:mime-version:content-type:content-type:
	 in-reply-to:in-reply-to:references:references;
	bh=Kuh3zkbT46KY8GMb0rTgXXajaVWrrSiQGGyKLuTLBEc=;
	b=OYXYP4DZ3Tyqek/6vfsI71lm64Y95sDmWH8QH+YsWsKPicrJzftZsF7DILSjHSD40aCPIk
	y5TRp9Kn3BdTlNbmSPk8DoX3pb6QplaYGOluDnHCYVijo4+HUNtY3gMrJlhxKoUmr8qQUS
	CO5zkWnwceSFTUw6Ktgl1RwZ65BfDP0=
Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by
 relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id
 us-mta-443-gvd1X6GrNgedrV2I4ORJew-1; Fri, 11 Aug 2023 06:17:21 -0400
X-MC-Unique: gvd1X6GrNgedrV2I4ORJew-1
Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1])
	(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
	(No client certificate requested)
	by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 437853C0ED57;
	Fri, 11 Aug 2023 10:17:21 +0000 (UTC)
Received: from oldenburg.str.redhat.com (unknown [10.2.16.14])
	by smtp.corp.redhat.com (Postfix) with ESMTPS id 6CC5340C206F;
	Fri, 11 Aug 2023 10:17:20 +0000 (UTC)
From: Florian Weimer <fweimer@redhat.com>
To: Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Subject: Re: [PATCH v7 1/8] arm: Add the clone3 wrapper
References: <20230803163558.991832-1-adhemerval.zanella@linaro.org>
	<20230803163558.991832-2-adhemerval.zanella@linaro.org>
Date: Fri, 11 Aug 2023 12:17:18 +0200
In-Reply-To: <20230803163558.991832-2-adhemerval.zanella@linaro.org>
	(Adhemerval Zanella via Libc-alpha's message of "Thu, 3 Aug 2023
	13:35:51 -0300")
Message-ID: <878rahx4r5.fsf@oldenburg.str.redhat.com>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux)
MIME-Version: 1.0
X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1
X-Mimecast-Spam-Score: 0
X-Mimecast-Originator: redhat.com
Content-Type: text/plain
X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP 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: <libc-alpha.sourceware.org>

* Adhemerval Zanella via Libc-alpha:

> +	/* Do the syscall, the kernel expects:
> +	   r7: system call number:
> +	   r0: cl_args
> +	   r1: size  */
> +	push    { r7 }
> +	cfi_adjust_cfa_offset (4)
> +	cfi_rel_offset (r7, 0)
> +	ldr     r7, =SYS_ify(clone3)
> +	swi	0x0
> +	cfi_endproc
> +
> +	cmp	r0, #0
> +	beq	1f
> +	pop     {r7}

> +1:
> +	.fnstart
> +	.cantunwind
> +	mov	r0, r3
> +	mov	ip, r2
> +	BLX (ip)

I think the stack is misaligned at the BNLX call because only one 4-byte
register is pushed.

Thanks,
Florian