| Message ID | 1403800214-28416-1-git-send-email-ian.campbell@citrix.com |
|---|---|
| State | Accepted |
| Commit | c0726c18e8135f87a5a5793d993d6bea1e3fa925 |
| Headers | show |
Hi Ian, On 06/26/2014 05:30 PM, Ian Campbell wrote: > By using -mgeneral-regs-only which is the Aarch64 equivalent to > -msoft-float. > > Otherwise gcc will corrupt the d* registers, which we don't save/restore when > trapping to/from the hypervisor. > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Julien Grall <julien.grall@linaro.org> > --- > Needless to say I consider this important for 4.4 backport... +1. I'm a bit surprised that it doesn't happen often. Regards,
>>> On 26.06.14 at 18:30, <ian.campbell@citrix.com> wrote: > By using -mgeneral-regs-only which is the Aarch64 equivalent to > -msoft-float. > > Otherwise gcc will corrupt the d* registers, which we don't save/restore > when > trapping to/from the hypervisor. > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com> > --- > Needless to say I consider this important for 4.4 backport... Agreed - for a fix like this I'm not even certain you'd need to wait for it to make it through the master push gate. Jan
On Fri, 2014-06-27 at 09:07 +0100, Jan Beulich wrote: > >>> On 26.06.14 at 18:30, <ian.campbell@citrix.com> wrote: > > By using -mgeneral-regs-only which is the Aarch64 equivalent to > > -msoft-float. > > > > Otherwise gcc will corrupt the d* registers, which we don't save/restore > > when > > trapping to/from the hypervisor. > > > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com> > > --- > > Needless to say I consider this important for 4.4 backport... > > Agreed - for a fix like this I'm not even certain you'd need to wait for > it to make it through the master push gate. Since the push gate doesn't even test arm64 at the moment I was certainly planning to skip that delay, yes. (and I would have considered it even if it was being tested...) Ian.
diff --git a/xen/arch/arm/Rules.mk b/xen/arch/arm/Rules.mk index 76b35d9..b5bf5cb 100644 --- a/xen/arch/arm/Rules.mk +++ b/xen/arch/arm/Rules.mk @@ -28,6 +28,7 @@ endif ifeq ($(TARGET_SUBARCH),arm64) CFLAGS += -mcpu=generic +CFLAGS += -mgeneral-regs-only # No fp registers etc arm32 := n arm64 := y endif
By using -mgeneral-regs-only which is the Aarch64 equivalent to -msoft-float. Otherwise gcc will corrupt the d* registers, which we don't save/restore when trapping to/from the hypervisor. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> --- Needless to say I consider this important for 4.4 backport... --- xen/arch/arm/Rules.mk | 1 + 1 file changed, 1 insertion(+)