From a78d777c869829a3f0320e1793adb44fb57ac950 Mon Sep 17 00:00:00 2001 From: James Yang Date: Tue, 18 Feb 2014 15:32:43 -0600 Subject: [PATCH] powerpc64: fix 64-bit process detection on embedded * syscall.c (get_scno) [POWERPC64]: Fix 64-bit process detection on embedded powerpc. Signed-off-by: James Yang Signed-off-by: Dmitry V. Levin --- syscall.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/syscall.c b/syscall.c index 4b6b4eb0..a0cc3127 100644 --- a/syscall.c +++ b/syscall.c @@ -1218,12 +1218,13 @@ get_scno(struct tcb *tcp) # ifdef POWERPC64 int currpers; - /* Check for 64/32 bit mode. */ - /* SF is bit 0 of MSR */ - if ((ppc_regs.msr >> 63) & 1) - currpers = 0; - else - currpers = 1; + /* + * Check for 64/32 bit mode. + * Embedded implementations covered by Book E extension of PPC use + * bit 0 (CM) of 32-bit Machine state register (MSR). + * Other implementations use bit 0 (SF) of 64-bit MSR. + */ + currpers = (ppc_regs.msr & 0x8000000080000000) ? 0 : 1; update_personality(tcp, currpers); # endif #elif defined(AVR32)