From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: Re: [PATCH 2/4] xen/arm64: do not clobber callee saved register in early_putch Date: Mon, 13 May 2013 17:53:00 +0100 Message-ID: References: <1368462160.537.125.camel@zakaz.uk.xensource.com> <1368462182-10317-2-git-send-email-ian.campbell@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1368462182-10317-2-git-send-email-ian.campbell@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: Julien Grall , Stefano Stabellini , "Tim (Xen.org)" , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On Mon, 13 May 2013, Ian Campbell wrote: > x23 is callee saved in the ARM 64 bit calling convention. Use x15 instead > which is a temporary register which need not be preserved. > > Fixes a random crash during boot. > > Signed-off-by: Ian Campbell Acked-by: Stefano Stabellini > xen/arch/arm/arm64/debug.S | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/xen/arch/arm/arm64/debug.S b/xen/arch/arm/arm64/debug.S > index f0c7761..38b7c74 100644 > --- a/xen/arch/arm/arm64/debug.S > +++ b/xen/arch/arm/arm64/debug.S > @@ -27,9 +27,9 @@ > /* Print a character on the UART - this function is called by C > * x0: character to print */ > early_putch: > - ldr x23, =FIXMAP_ADDR(FIXMAP_CONSOLE) > - early_uart_ready x23, 1 > - early_uart_transmit x23, w0 > + ldr x15, =FIXMAP_ADDR(FIXMAP_CONSOLE) > + early_uart_ready x15, 1 > + early_uart_transmit x15, w0 > ret > > /* > -- > 1.7.2.5 >