We need to load cr0 to have access to all fprs during save and restore of fprs. Saving conditionally on basis of the CR0 AFP bit would be a pain. Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> --- s390x/cstart64.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/s390x/cstart64.S b/s390x/cstart64.S index 8e2b21e..043e34a 100644 --- a/s390x/cstart64.S +++ b/s390x/cstart64.S @@ -94,7 +94,7 @@ memsetxc: stmg %r0, %r15, GEN_LC_SW_INT_GRS /* save cr0 */ stctg %c0, %c0, GEN_LC_SW_INT_CR0 - /* load initial cr0 again */ + /* load a cr0 that has the AFP control bit which enables all FPRs */ larl %r1, initial_cr0 lctlg %c0, %c0, 0(%r1) /* save fprs 0-15 + fpc */ @@ -139,7 +139,7 @@ diag308_load_reset: xgr %r2, %r2 br %r14 /* Success path */ - /* We lost cr0 due to the reset */ + /* load a cr0 that has the AFP control bit which enables all FPRs */ 0: larl %r1, initial_cr0 lctlg %c0, %c0, 0(%r1) RESTORE_REGS -- 2.20.1
