diff options
| author | Anton Lindqvist <anton@cvs.openbsd.org> | 2023-07-05 18:23:11 +0000 |
|---|---|---|
| committer | Anton Lindqvist <anton@cvs.openbsd.org> | 2023-07-05 18:23:11 +0000 |
| commit | 205f38591802247882a1aac84b2e8c56acd07702 (patch) | |
| tree | 251012da26477537fffbff78078ad788be4f194d | |
| parent | 99326b8dcc01239c320c1338997604e259ad413b (diff) | |
The hypercall page populated with instructions by the hypervisor is not IBT
compatible due to lack of endbr64. Replace the indirect call with a new
hv_hypercall_trampoline() routine which jumps to the hypercall page without any
indirection.
Allows me to boot OpenBSD using Hyper-V on Windows 11 again.
ok guenther@
| -rw-r--r-- | sys/arch/amd64/amd64/locore.S | 24 | ||||
| -rw-r--r-- | sys/dev/pv/hyperv.c | 5 |
2 files changed, 18 insertions, 11 deletions
diff --git a/sys/arch/amd64/amd64/locore.S b/sys/arch/amd64/amd64/locore.S index 677c816d6f9..ec41559e6bf 100644 --- a/sys/arch/amd64/amd64/locore.S +++ b/sys/arch/amd64/amd64/locore.S @@ -1,4 +1,4 @@ -/* $OpenBSD: locore.S,v 1.134 2023/04/17 00:14:59 deraadt Exp $ */ +/* $OpenBSD: locore.S,v 1.135 2023/07/05 18:23:10 anton Exp $ */ /* $NetBSD: locore.S,v 1.13 2004/03/25 18:33:17 drochner Exp $ */ /* @@ -1149,20 +1149,28 @@ NENTRY(rdmsr_resume) lfence END(rdmsr_safe) -#if NXEN > 0 +#if NHYPERV > 0 +/* uint64_t hv_hypercall_trampoline(uint64_t control, paddr_t input, paddr_t output) */ +NENTRY(hv_hypercall_trampoline) + endbr64 + mov %rdx, %r8 + mov %rsi, %rdx + mov %rdi, %rcx + jmp hv_hypercall_page +END(hv_hypercall_trampoline) /* Hypercall page needs to be page aligned */ .text .align NBPG, 0xcc - .globl xen_hypercall_page -xen_hypercall_page: + .globl hv_hypercall_page +hv_hypercall_page: .skip 0x1000, 0xcc -#endif /* NXEN > 0 */ +#endif /* NHYPERV > 0 */ -#if NHYPERV > 0 +#if NXEN > 0 /* Hypercall page needs to be page aligned */ .text .align NBPG, 0xcc - .globl hv_hypercall_page -hv_hypercall_page: + .globl xen_hypercall_page +xen_hypercall_page: .skip 0x1000, 0xcc #endif /* NXEN > 0 */ diff --git a/sys/dev/pv/hyperv.c b/sys/dev/pv/hyperv.c index 08a713d814d..da9bf3ae6d7 100644 --- a/sys/dev/pv/hyperv.c +++ b/sys/dev/pv/hyperv.c @@ -407,9 +407,8 @@ hv_hypercall(struct hv_softc *sc, uint64_t control, void *input, } #ifdef __amd64__ - __asm__ volatile ("mov %0, %%r8" : : "r" (output_pa) : "r8"); - __asm__ volatile ("call *%3" : "=a" (status) : "c" (control), - "d" (input_pa), "m" (sc->sc_hc)); + extern uint64_t hv_hypercall_trampoline(uint64_t, paddr_t, paddr_t); + status = hv_hypercall_trampoline(control, input_pa, output_pa); #else /* __i386__ */ { uint32_t control_hi = control >> 32; |