Am 27.06.24 um 11:57 schrieb Heiko Carstens:
On Thu, Jun 27, 2024 at 11:05:20AM +0200, Christian Borntraeger wrote:in rare cases, e.g. for injecting a machine check we do intercept all load PSW instructions via ICTL_LPSW. With facility 193 a new variant LPSWEY was added. KVM needs to handle that as well. Fixes: a3efa8429266 ("KVM: s390: gen_facilities: allow facilities 165, 193, 194 and 196") Reported-by: Marc Hartmayer <mhartmay@xxxxxxxxxxxxx> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> --- arch/s390/include/asm/kvm_host.h | 1 + arch/s390/kvm/kvm-s390.c | 1 + arch/s390/kvm/kvm-s390.h | 16 ++++++++++++++++ arch/s390/kvm/priv.c | 32 ++++++++++++++++++++++++++++++++ 4 files changed, 50 insertions(+)...+static inline u64 kvm_s390_get_base_disp_siy(struct kvm_vcpu *vcpu, u8 *ar) +{ + u32 base1 = vcpu->arch.sie_block->ipb >> 28; + u32 disp1 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16) + + ((vcpu->arch.sie_block->ipb & 0xff00) << 4); + + /* The displacement is a 20bit _SIGNED_ value */ + if (disp1 & 0x80000) + disp1+=0xfff00000; + + if (ar) + *ar = base1; + + return (base1 ? vcpu->run->s.regs.gprs[base1] : 0) + (long)(int)disp1; +}You may want to use sign_extend32() or sign_extend64() instead of open-coding.
Something like sign_extend64(disp1, 31) I actually find that harder to read, but I am open for other opinions.
