From: Hendrik Brueckner Date: Tue, 19 Nov 2013 11:26:09 +0000 (+0100) Subject: s390/signal: always restore saved runtime instrumentation psw bit X-Git-Tag: accepted/tizen/common/20141203.182822~1001^2~6 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=aa7e04b3808614980d474735cdb0bf35ac5cdf26;p=platform%2Fkernel%2Flinux-arm64.git s390/signal: always restore saved runtime instrumentation psw bit Commit "s390: fix handling of runtime instrumentation psw bit" (5ebf250dab) changed the behavior of setting the runtime instrumentation psw bit. This commit restores the original logic: 1. When returning from the signal handler, the runtime instrumentation psw bit is restored to its saved state. 2. If the runtime instrumentation psw bit is enabled during the signal handler, it is always turned off when leaving the signal handler. The saved state is restored as described in 1. That also implies that turning on runtime instrumentation in the signal handler is only effective while running in the signal context. Signed-off-by: Hendrik Brueckner --- diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c index 6e24429..95e7ba0 100644 --- a/arch/s390/kernel/compat_signal.c +++ b/arch/s390/kernel/compat_signal.c @@ -194,7 +194,7 @@ static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs) return -EINVAL; /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */ - regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) | + regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) | (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_USER) << 32 | (__u64)(user_sregs.regs.psw.mask & PSW32_MASK_RI) << 32 | (__u64)(user_sregs.regs.psw.addr & PSW32_ADDR_AMODE); diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c index fb53587..d8fd508 100644 --- a/arch/s390/kernel/signal.c +++ b/arch/s390/kernel/signal.c @@ -94,7 +94,7 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) return -EINVAL; /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */ - regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) | + regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) | (user_sregs.regs.psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); /* Check for invalid user address space control. */ if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME)