diff options
| -rw-r--r-- | arch/x86/include/asm/lguest_hcall.h | 29 | ||||
| -rw-r--r-- | arch/x86/lguest/boot.c | 61 | ||||
| -rw-r--r-- | arch/x86/lguest/i386_head.S | 2 | ||||
| -rw-r--r-- | drivers/lguest/lguest_device.c | 4 | ||||
| -rw-r--r-- | drivers/lguest/x86/core.c | 12 |
5 files changed, 68 insertions, 40 deletions
diff --git a/arch/x86/include/asm/lguest_hcall.h b/arch/x86/include/asm/lguest_hcall.h index ba0eed8aa1a6..b60f2924c413 100644 --- a/arch/x86/include/asm/lguest_hcall.h +++ b/arch/x86/include/asm/lguest_hcall.h @@ -28,22 +28,39 @@ #ifndef __ASSEMBLY__ #include <asm/hw_irq.h> -#include <asm/kvm_para.h> /*G:030 * But first, how does our Guest contact the Host to ask for privileged * operations? There are two ways: the direct way is to make a "hypercall", * to make requests of the Host Itself. * - * We use the KVM hypercall mechanism, though completely different hypercall - * numbers. Seventeen hypercalls are available: the hypercall number is put in - * the %eax register, and the arguments (when required) are placed in %ebx, - * %ecx, %edx and %esi. If a return value makes sense, it's returned in %eax. + * Our hypercall mechanism uses the highest unused trap code (traps 32 and + * above are used by real hardware interrupts). Seventeen hypercalls are + * available: the hypercall number is put in the %eax register, and the + * arguments (when required) are placed in %ebx, %ecx, %edx and %esi. + * If a return value makes sense, it's returned in %eax. * * Grossly invalid calls result in Sudden Death at the hands of the vengeful * Host, rather than returning failure. This reflects Winston Churchill's * definition of a gentleman: "someone who is only rude intentionally". -:*/ + */ +static inline unsigned long +hcall(unsigned long call, + unsigned long arg1, unsigned long arg2, unsigned long arg3, + unsigned long arg4) +{ + /* "int" is the Intel instruction to trigger a trap. */ + asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY) + /* The call in %eax (aka "a") might be overwritten */ + : "=a"(call) + /* The arguments are in %eax, %ebx, %ecx, %edx & %esi */ + : "a"(call), "b"(arg1), "c"(arg2), "d"(arg3), "S"(arg4) + /* "memory" means this might write somewhere in memory. + * This isn't true for all calls, but it's safe to tell + * gcc that it might happen so it doesn't get clever. */ + : "memory"); + return call; +} /* Can't use our min() macro here: needs to be a constant */ #define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32) diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 7e59dc1d3fc2..2bdf628066bd 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -115,7 +115,7 @@ static void async_hcall(unsigned long call, unsigned long arg1, local_irq_save(flags); if (lguest_data.hcall_status[next_call] != 0xFF) { /* Table full, so do normal hcall which will flush table. */ - kvm_hypercall4(call, arg1, arg2, arg3, arg4); + hcall(call, arg1, arg2, arg3, arg4); } else { lguest_data.hcalls[next_call].arg0 = call; lguest_data.hcalls[next_call].arg1 = arg1; @@ -145,46 +145,45 @@ static void async_hcall(unsigned long call, unsigned long arg1, * So, when we're in lazy mode, we call async_hcall() to store the call for * future processing: */ -static void lazy_hcall1(unsigned long call, - unsigned long arg1) +static void lazy_hcall1(unsigned long call, unsigned long arg1) { if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) - kvm_hypercall1(call, arg1); + hcall(call, arg1, 0, 0, 0); else async_hcall(call, arg1, 0, 0, 0); } /* You can imagine what lazy_hcall2, 3 and 4 look like. :*/ static void lazy_hcall2(unsigned long call, - unsigned long arg1, - unsigned long arg2) + unsigned long arg1, + unsigned long arg2) { if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) - kvm_hypercall2(call, arg1, arg2); + hcall(call, arg1, arg2, 0, 0); else async_hcall(call, arg1, arg2, 0, 0); } static void lazy_hcall3(unsigned long call, - unsigned long arg1, - unsigned long arg2, - unsigned long arg3) + unsigned long arg1, + unsigned long arg2, + unsigned long arg3) { if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) - kvm_hypercall3(call, arg1, arg2, arg3); + hcall(call, arg1, arg2, arg3, 0); else async_hcall(call, arg1, arg2, arg3, 0); } #ifdef CONFIG_X86_PAE static void lazy_hcall4(unsigned long call, - unsigned long arg1, - unsigned long arg2, - unsigned long arg3, - unsigned long arg4) + unsigned long arg1, + unsigned long arg2, + unsigned long arg3, + unsigned long arg4) { if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) - kvm_hypercall4(call, arg1, arg2, arg3, arg4); + hcall(call, arg1, arg2, arg3, arg4); else async_hcall(call, arg1, arg2, arg3, arg4); } @@ -196,13 +195,13 @@ static void lazy_hcall4(unsigned long call, :*/ static void lguest_leave_lazy_mmu_mode(void) { - kvm_hypercall0(LHCALL_FLUSH_ASYNC); + hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0); paravirt_leave_lazy_mmu(); } static void lguest_end_context_switch(struct task_struct *next) { - kvm_hypercall0(LHCALL_FLUSH_ASYNC); + hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0); paravirt_end_context_switch(next); } @@ -286,7 +285,7 @@ static void lguest_write_idt_entry(gate_desc *dt, /* Keep the local copy up to date. */ native_write_idt_entry(dt, entrynum, g); /* Tell Host about this new entry. */ - kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1]); + hcall(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1], 0); } /* @@ -300,7 +299,7 @@ static void lguest_load_idt(const struct desc_ptr *desc) struct desc_struct *idt = (void *)desc->address; for (i = 0; i < (desc->size+1)/8; i++) - kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b); + hcall(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b, 0); } /* @@ -321,7 +320,7 @@ static void lguest_load_gdt(const struct desc_ptr *desc) struct desc_struct *gdt = (void *)desc->address; for (i = 0; i < (desc->size+1)/8; i++) - kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b); + hcall(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b, 0); } /* @@ -334,8 +333,8 @@ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum, { native_write_gdt_entry(dt, entrynum, desc, type); /* Tell Host about this new entry. */ - kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, entrynum, - dt[entrynum].a, dt[entrynum].b); + hcall(LHCALL_LOAD_GDT_ENTRY, entrynum, + dt[entrynum].a, dt[entrynum].b, 0); } /* @@ -931,7 +930,7 @@ static int lguest_clockevent_set_next_event(unsigned long delta, } /* Please wake us this far in the future. */ - kvm_hypercall1(LHCALL_SET_CLOCKEVENT, delta); + hcall(LHCALL_SET_CLOCKEVENT, delta, 0, 0, 0); return 0; } @@ -942,7 +941,7 @@ static void lguest_clockevent_set_mode(enum clock_event_mode mode, case CLOCK_EVT_MODE_UNUSED: case CLOCK_EVT_MODE_SHUTDOWN: /* A 0 argument shuts the clock down. */ - kvm_hypercall0(LHCALL_SET_CLOCKEVENT); + hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0); break; case CLOCK_EVT_MODE_ONESHOT: /* This is what we expect. */ @@ -1100,7 +1099,7 @@ static void set_lguest_basic_apic_ops(void) /* STOP! Until an interrupt comes in. */ static void lguest_safe_halt(void) { - kvm_hypercall0(LHCALL_HALT); + hcall(LHCALL_HALT, 0, 0, 0, 0); } /* @@ -1112,8 +1111,8 @@ static void lguest_safe_halt(void) */ static void lguest_power_off(void) { - kvm_hypercall2(LHCALL_SHUTDOWN, __pa("Power down"), - LGUEST_SHUTDOWN_POWEROFF); + hcall(LHCALL_SHUTDOWN, __pa("Power down"), + LGUEST_SHUTDOWN_POWEROFF, 0, 0); } /* @@ -1123,7 +1122,7 @@ static void lguest_power_off(void) */ static int lguest_panic(struct notifier_block *nb, unsigned long l, void *p) { - kvm_hypercall2(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF); + hcall(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF, 0, 0); /* The hcall won't return, but to keep gcc happy, we're "done". */ return NOTIFY_DONE; } @@ -1162,7 +1161,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count) len = sizeof(scratch) - 1; scratch[len] = '\0'; memcpy(scratch, buf, len); - kvm_hypercall1(LHCALL_NOTIFY, __pa(scratch)); + hcall(LHCALL_NOTIFY, __pa(scratch), 0, 0, 0); /* This routine returns the number of bytes actually written. */ return len; @@ -1174,7 +1173,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count) */ static void lguest_restart(char *reason) { - kvm_hypercall2(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART); + hcall(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART, 0, 0); } /*G:050 diff --git a/arch/x86/lguest/i386_head.S b/arch/x86/lguest/i386_head.S index 27eac0faee48..4f420c2f2d55 100644 --- a/arch/x86/lguest/i386_head.S +++ b/arch/x86/lguest/i386_head.S @@ -32,7 +32,7 @@ ENTRY(lguest_entry) */ movl $LHCALL_LGUEST_INIT, %eax movl $lguest_data - __PAGE_OFFSET, %ebx - .byte 0x0f,0x01,0xc1 /* KVM_HYPERCALL */ + int $LGUEST_TRAP_ENTRY /* Set up the initial stack so we can run C code. */ movl $(init_thread_union+THREAD_SIZE),%esp diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c index 07090f379c63..69c84a1d88ea 100644 --- a/drivers/lguest/lguest_device.c +++ b/drivers/lguest/lguest_device.c @@ -178,7 +178,7 @@ static void set_status(struct virtio_device *vdev, u8 status) /* We set the status. */ to_lgdev(vdev)->desc->status = status; - kvm_hypercall1(LHCALL_NOTIFY, (max_pfn << PAGE_SHIFT) + offset); + hcall(LHCALL_NOTIFY, (max_pfn << PAGE_SHIFT) + offset, 0, 0, 0); } static void lg_set_status(struct virtio_device *vdev, u8 status) @@ -229,7 +229,7 @@ static void lg_notify(struct virtqueue *vq) */ struct lguest_vq_info *lvq = vq->priv; - kvm_hypercall1(LHCALL_NOTIFY, lvq->config.pfn << PAGE_SHIFT); + hcall(LHCALL_NOTIFY, lvq->config.pfn << PAGE_SHIFT, 0, 0, 0); } /* An extern declaration inside a C file is bad form. Don't do it. */ diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index fb2b7ef7868e..b4eb675a807e 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -288,6 +288,18 @@ static int emulate_insn(struct lg_cpu *cpu) insn = lgread(cpu, physaddr, u8); /* + * Around 2.6.33, the kernel started using an emulation for the + * cmpxchg8b instruction in early boot on many configurations. This + * code isn't paravirtualized, and it tries to disable interrupts. + * Ignore it, which will Mostly Work. + */ + if (insn == 0xfa) { + /* "cli", or Clear Interrupt Enable instruction. Skip it. */ + cpu->regs->eip++; + return 1; + } + + /* * 0x66 is an "operand prefix". It means it's using the upper 16 bits * of the eax register. */ |
