s390/mcck: move register validation to C code (5fa2ea07) · Commits · EulixOS / Software / Kernel

arch/s390/include/asm/ctl_reg.h

+0 −2

Original line number	Diff line number	Diff line
		@@ -21,8 +21,6 @@
		#define CR0_INTERRUPT_KEY_SUBMASK BIT(63 - 57)
		#define CR0_MEASUREMENT_ALERT_SUBMASK BIT(63 - 58)

		#define CR2_GUARDED_STORAGE BIT(63 - 59)

		#define CR14_UNUSED_32 BIT(63 - 32)
		#define CR14_UNUSED_33 BIT(63 - 33)
		#define CR14_CHANNEL_REPORT_SUBMASK BIT(63 - 35)

arch/s390/kernel/asm-offsets.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -14,8 +14,6 @@
		#include <linux/pgtable.h>
		#include <asm/idle.h>
		#include <asm/gmap.h>
		#include <asm/nmi.h>
		#include <asm/setup.h>
		#include <asm/stacktrace.h>

		int main(void)
		@@ -108,7 +106,6 @@ int main(void)
		OFFSET(__LC_LAST_UPDATE_CLOCK, lowcore, last_update_clock);
		OFFSET(__LC_INT_CLOCK, lowcore, int_clock);
		OFFSET(__LC_MCCK_CLOCK, lowcore, mcck_clock);
		OFFSET(__LC_CLOCK_COMPARATOR, lowcore, clock_comparator);
		OFFSET(__LC_BOOT_CLOCK, lowcore, boot_clock);
		OFFSET(__LC_CURRENT, lowcore, current_task);
		OFFSET(__LC_KERNEL_STACK, lowcore, kernel_stack);
		@@ -145,9 +142,6 @@ int main(void)
		OFFSET(__LC_CREGS_SAVE_AREA, lowcore, cregs_save_area);
		OFFSET(__LC_PGM_TDB, lowcore, pgm_tdb);
		BLANK();
		/* extended machine check save area */
		OFFSET(__MCESA_GS_SAVE_AREA, mcesa, guarded_storage_save_area);
		BLANK();
		/* gmap/sie offsets */
		OFFSET(__GMAP_ASCE, gmap, asce);
		OFFSET(__SIE_PROG0C, kvm_s390_sie_block, prog0c);

arch/s390/kernel/entry.S

+1 −38

Original line number	Diff line number	Diff line
		@@ -14,7 +14,6 @@
		#include <asm/alternative-asm.h>
		#include <asm/processor.h>
		#include <asm/cache.h>
		#include <asm/ctl_reg.h>
		#include <asm/dwarf.h>
		#include <asm/errno.h>
		#include <asm/ptrace.h>
		@@ -506,8 +505,6 @@ ENTRY(mcck_int_handler)
		BPOFF
		la %r1,4095 # validate r1
		spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # validate cpu timer
		sckc __LC_CLOCK_COMPARATOR # validate comparator
		lam %a0,%a15,__LC_AREGS_SAVE_AREA-4095(%r1) # validate acrs
		lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# validate gprs
		lg %r12,__LC_CURRENT
		lmg %r8,%r9,__LC_MCK_OLD_PSW
		@@ -518,41 +515,7 @@ ENTRY(mcck_int_handler)
		la %r14,4095
		lctlg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r14) # validate ctl regs
		ptlb
		lg %r11,__LC_MCESAD-4095(%r14) # extended machine check save area
		nill %r11,0xfc00 # MCESA_ORIGIN_MASK
		TSTMSK __LC_CREGS_SAVE_AREA+16-4095(%r14),CR2_GUARDED_STORAGE
		jno 0f
		TSTMSK __LC_MCCK_CODE,MCCK_CODE_GS_VALID
		jno 0f
		.insn rxy,0xe3000000004d,0,__MCESA_GS_SAVE_AREA(%r11) # LGSC
		0: l %r14,__LC_FP_CREG_SAVE_AREA-4095(%r14)
		TSTMSK __LC_MCCK_CODE,MCCK_CODE_FC_VALID
		jo 0f
		sr %r14,%r14
		0: sfpc %r14
		TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
		jo 0f
		lghi %r14,__LC_FPREGS_SAVE_AREA
		ld %f0,0(%r14)
		ld %f1,8(%r14)
		ld %f2,16(%r14)
		ld %f3,24(%r14)
		ld %f4,32(%r14)
		ld %f5,40(%r14)
		ld %f6,48(%r14)
		ld %f7,56(%r14)
		ld %f8,64(%r14)
		ld %f9,72(%r14)
		ld %f10,80(%r14)
		ld %f11,88(%r14)
		ld %f12,96(%r14)
		ld %f13,104(%r14)
		ld %f14,112(%r14)
		ld %f15,120(%r14)
		j 1f
		0: VLM %v0,%v15,0,%r11
		VLM %v16,%v31,256,%r11
		1: lghi %r14,__LC_CPU_TIMER_SAVE_AREA
		lghi %r14,__LC_CPU_TIMER_SAVE_AREA
		mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
		TSTMSK __LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID
		jo 3f

arch/s390/kernel/nmi.c

+77 −8

Original line number	Diff line number	Diff line
		@@ -189,12 +189,16 @@ void noinstr s390_handle_mcck(void)
		* returns 0 if all required registers are available
		* returns 1 otherwise
		*/
		static int notrace s390_check_registers(union mci mci, int umode)
		static int notrace s390_validate_registers(union mci mci, int umode)
		{
		struct mcesa *mcesa;
		void *fpt_save_area;
		union ctlreg2 cr2;
		int kill_task;
		u64 zero;

		kill_task = 0;
		zero = 0;

		if (!mci.gr) {
		/*
		@@ -217,35 +221,89 @@ static int notrace s390_check_registers(union mci mci, int umode)
		if (!test_cpu_flag(CIF_FPU))
		kill_task = 1;
		}
		fpt_save_area = &S390_lowcore.floating_pt_save_area;
		if (!mci.fc) {
		/*
		* Floating point control register can't be restored.
		* If the kernel currently uses the floating pointer
		* registers and needs the FPC register the system is
		* stopped. If the process has its floating pointer
		* registers loaded it is terminated.
		* registers loaded it is terminated. Otherwise the
		* FPC is just validated.
		*/
		if (S390_lowcore.fpu_flags & KERNEL_FPC)
		s390_handle_damage();
		asm volatile(
		" lfpc %0\n"
		:
		: "Q" (zero));
		if (!test_cpu_flag(CIF_FPU))
		kill_task = 1;
		}
		} else {
		asm volatile(
		" lfpc %0\n"
		:
		: "Q" (S390_lowcore.fpt_creg_save_area));
		}

		mcesa = (struct mcesa *)(S390_lowcore.mcesad & MCESA_ORIGIN_MASK);
		if (!MACHINE_HAS_VX) {
		/* Validate floating point registers */
		asm volatile(
		" ld 0,0(%0)\n"
		" ld 1,8(%0)\n"
		" ld 2,16(%0)\n"
		" ld 3,24(%0)\n"
		" ld 4,32(%0)\n"
		" ld 5,40(%0)\n"
		" ld 6,48(%0)\n"
		" ld 7,56(%0)\n"
		" ld 8,64(%0)\n"
		" ld 9,72(%0)\n"
		" ld 10,80(%0)\n"
		" ld 11,88(%0)\n"
		" ld 12,96(%0)\n"
		" ld 13,104(%0)\n"
		" ld 14,112(%0)\n"
		" ld 15,120(%0)\n"
		:
		: "a" (fpt_save_area)
		: "memory");
		} else {
		/* Validate vector registers */
		union ctlreg0 cr0;

		if (MACHINE_HAS_VX) {
		if (!mci.vr) {
		/*
		* Vector registers can't be restored. If the kernel
		* currently uses vector registers the system is
		* stopped. If the process has its vector registers
		* loaded it is terminated.
		* loaded it is terminated. Otherwise just validate
		* the registers.
		*/
		if (S390_lowcore.fpu_flags & KERNEL_VXR)
		s390_handle_damage();
		if (!test_cpu_flag(CIF_FPU))
		kill_task = 1;
		}
		}
		/* Check if access registers are valid */
		cr0.val = S390_lowcore.cregs_save_area[0];
		cr0.afp = cr0.vx = 1;
		__ctl_load(cr0.val, 0, 0);
		asm volatile(
		" la 1,%0\n"
		" .word 0xe70f,0x1000,0x0036\n" /* vlm 0,15,0(1) */
		" .word 0xe70f,0x1100,0x0c36\n" /* vlm 16,31,256(1) */
		:
		: "Q" ((struct vx_array )mcesa->vector_save_area)
		: "1");
		__ctl_load(S390_lowcore.cregs_save_area[0], 0, 0);
		}
		/* Validate access registers */
		asm volatile(
		" lam 0,15,0(%0)\n"
		:
		: "a" (&S390_lowcore.access_regs_save_area)
		: "memory");
		if (!mci.ar) {
		/*
		* Access registers have unknown contents.
		@@ -253,7 +311,7 @@ static int notrace s390_check_registers(union mci mci, int umode)
		*/
		kill_task = 1;
		}
		/* Check guarded storage registers */
		/* Validate guarded storage registers */
		cr2.val = S390_lowcore.cregs_save_area[2];
		if (cr2.gse) {
		if (!mci.gs) {
		@@ -263,15 +321,26 @@ static int notrace s390_check_registers(union mci mci, int umode)
		* It has to be terminated.
		*/
		kill_task = 1;
		} else {
		load_gs_cb((struct gs_cb *)mcesa->guarded_storage_save_area);
		}
		}
		/*
		* The getcpu vdso syscall reads CPU number from the programmable
		* field of the TOD clock. Disregard the TOD programmable register
		* validity bit and load the CPU number into the TOD programmable
		* field unconditionally.
		*/
		set_tod_programmable_field(raw_smp_processor_id());
		/* Validate clock comparator register */
		set_clock_comparator(S390_lowcore.clock_comparator);

		if (!mci.ms \|\| !mci.pm \|\| !mci.ia)
		kill_task = 1;

		return kill_task;
		}
		NOKPROBE_SYMBOL(s390_check_registers);
		NOKPROBE_SYMBOL(s390_validate_registers);

		/*
		* Backup the guest's machine check info to its description block
		@@ -369,7 +438,7 @@ int notrace s390_do_machine_check(struct pt_regs *regs)
		s390_handle_damage();
		}
		}
		if (s390_check_registers(mci, user_mode(regs))) {
		if (s390_validate_registers(mci, user_mode(regs))) {
		/*
		* Couldn't restore all register contents for the
		* user space process -> mark task for termination.