[v4,8/8] x86/vm_event: Add HVM debug exception vm_events

Message ID	1464561430-13465-8-git-send-email-tamas@tklengyel.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <xen-devel-bounces@lists.xen.org> From: Tamas K Lengyel <tamas@tklengyel.com> To: xen-devel@lists.xenproject.org Date: Sun, 29 May 2016 16:37:10 -0600 Message-Id: <1464561430-13465-8-git-send-email-tamas@tklengyel.com> In-Reply-To: <1464561430-13465-1-git-send-email-tamas@tklengyel.com> References: <1464561430-13465-1-git-send-email-tamas@tklengyel.com> Cc: Kevin Tian <kevin.tian@intel.com>, Tamas K Lengyel <tamas@tklengyel.com>, Wei Liu <wei.liu2@citrix.com>, Jun Nakajima <jun.nakajima@intel.com>, Razvan Cojocaru <rcojocaru@bitdefender.com>, Andrew Cooper <andrew.cooper3@citrix.com>, Ian Jackson <ian.jackson@eu.citrix.com>, Jan Beulich <jbeulich@suse.com> Subject: [Xen-devel] [PATCH v4 8/8] x86/vm_event: Add HVM debug exception vm_events Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" <xen-devel-bounces@lists.xen.org>

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h index 3085130..29d983e 100644 --- a/tools/libxc/include/xenctrl.h +++ b/tools/libxc/include/xenctrl.h @@ -2162,7 +2162,8 @@ int xc_monitor_guest_request(xc_interface *xch, domid_t domain_id, bool enable, bool sync); int xc_monitor_privileged_call(xc_interface *xch, domid_t domain_id, bool enable); - +int xc_monitor_debug_exceptions(xc_interface *xch, domid_t domain_id, + bool enable, bool sync); /** * This function enables / disables emulation for each REP for a * REP-compatible instruction. diff --git a/tools/libxc/xc_monitor.c b/tools/libxc/xc_monitor.c index 1e4a9d2..b0bf708 100644 --- a/tools/libxc/xc_monitor.c +++ b/tools/libxc/xc_monitor.c @@ -171,6 +171,21 @@ int xc_monitor_privileged_call(xc_interface *xch, domid_t domain_id, return do_domctl(xch, &domctl); } +int xc_monitor_debug_exceptions(xc_interface *xch, domid_t domain_id, + bool enable, bool sync) +{ + DECLARE_DOMCTL; + + domctl.cmd = XEN_DOMCTL_monitor_op; + domctl.domain = domain_id; + domctl.u.monitor_op.op = enable ? XEN_DOMCTL_MONITOR_OP_ENABLE + : XEN_DOMCTL_MONITOR_OP_DISABLE; + domctl.u.monitor_op.event = XEN_DOMCTL_MONITOR_EVENT_DEBUG_EXCEPTION; + domctl.u.monitor_op.u.debug_exception.sync = sync; + + return do_domctl(xch, &domctl); +} + /* * Local variables: * mode: C diff --git a/tools/tests/xen-access/xen-access.c b/tools/tests/xen-access/xen-access.c index 1b2b3fd..8678ccd 100644 --- a/tools/tests/xen-access/xen-access.c +++ b/tools/tests/xen-access/xen-access.c @@ -52,6 +52,10 @@ #define ERROR(a, b...) fprintf(stderr, a "\n", ## b) #define PERROR(a, b...) fprintf(stderr, a ": %s\n", ## b, strerror(errno)) +/* From xen/include/asm-x86/processor.h */ +#define X86_TRAP_DEBUG 1 +#define X86_TRAP_INT3 3 + typedef struct vm_event { domid_t domain_id; xenevtchn_handle *xce_handle; @@ -332,7 +336,7 @@ void usage(char* progname) { fprintf(stderr, "Usage: %s [-m] <domain_id> write|exec", progname); #if defined(__i386__) || defined(__x86_64__) - fprintf(stderr, "|breakpoint|altp2m_write|altp2m_exec"); + fprintf(stderr, "|breakpoint|altp2m_write|altp2m_exec|debug"); #elif defined(__arm__) || defined(__aarch64__) fprintf(stderr, "|privcall"); #endif @@ -355,11 +359,13 @@ int main(int argc, char *argv[]) xc_interface *xch; xenmem_access_t default_access = XENMEM_access_rwx; xenmem_access_t after_first_access = XENMEM_access_rwx; + int memaccess = 0; int required = 0; int breakpoint = 0; int shutting_down = 0; int privcall = 0; int altp2m = 0; + int debug = 0; uint16_t altp2m_view_id = 0; char* progname = argv[0]; @@ -393,11 +399,13 @@ int main(int argc, char *argv[]) { default_access = XENMEM_access_rx; after_first_access = XENMEM_access_rwx; + memaccess = 1; } else if ( !strcmp(argv[0], "exec") ) { default_access = XENMEM_access_rw; after_first_access = XENMEM_access_rwx; + memaccess = 1; } #if defined(__i386__) || defined(__x86_64__) else if ( !strcmp(argv[0], "breakpoint") ) @@ -408,11 +416,17 @@ int main(int argc, char *argv[]) { default_access = XENMEM_access_rx; altp2m = 1; + memaccess = 1; } else if ( !strcmp(argv[0], "altp2m_exec") ) { default_access = XENMEM_access_rw; altp2m = 1; + memaccess = 1; + } + else if ( !strcmp(argv[0], "debug") ) + { + debug = 1; } #elif defined(__arm__) || defined(__aarch64__) else if ( !strcmp(argv[0], "privcall") ) @@ -453,7 +467,7 @@ int main(int argc, char *argv[]) } /* With altp2m we just create a new, restricted view of the memory */ - if ( altp2m ) + if ( memaccess && altp2m ) { xen_pfn_t gfn = 0; unsigned long perm_set = 0; @@ -500,7 +514,7 @@ int main(int argc, char *argv[]) } } - if ( !altp2m ) + if ( memaccess && !altp2m ) { /* Set the default access type and convert all pages to it */ rc = xc_set_mem_access(xch, domain_id, default_access, ~0ull, 0); @@ -541,6 +555,16 @@ int main(int argc, char *argv[]) } } + if ( debug ) + { + rc = xc_monitor_debug_exceptions(xch, domain_id, 1, 1); + if ( rc < 0 ) + { + ERROR("Error %d setting debug exception listener with vm_event\n", rc); + goto exit; + } + } + /* Wait for access */ for (;;) { @@ -551,9 +575,10 @@ int main(int argc, char *argv[]) if ( breakpoint ) rc = xc_monitor_software_breakpoint(xch, domain_id, 0); - if ( privcall ) rc = xc_monitor_privileged_call(xch, domain_id, 0); + if ( debug ) + rc = xc_monitor_debug_exceptions(xch, domain_id, 0, 0); if ( altp2m ) { @@ -661,9 +686,10 @@ int main(int argc, char *argv[]) req.vcpu_id); /* Reinject */ - rc = xc_hvm_inject_trap( - xch, domain_id, req.vcpu_id, 3, - HVMOP_TRAP_sw_exc, -1, 0, 0); + rc = xc_hvm_inject_trap(xch, domain_id, req.vcpu_id, + X86_TRAP_INT3, + req.u.software_breakpoint.type, -1, + req.u.software_breakpoint.insn_length, 0); if (rc < 0) { ERROR("Error %d injecting breakpoint\n", rc); @@ -711,6 +737,27 @@ int main(int argc, char *argv[]) rsp.flags |= VM_EVENT_FLAG_TOGGLE_SINGLESTEP; break; + case VM_EVENT_REASON_DEBUG_EXCEPTION: + printf("Debug exception: rip=%016"PRIx64", vcpu %d. Type: %u. Length: %u\n", + req.data.regs.x86.rip, + req.vcpu_id, + req.u.debug_exception.type, + req.u.debug_exception.insn_length); + + /* Reinject */ + rc = xc_hvm_inject_trap(xch, domain_id, req.vcpu_id, + X86_TRAP_DEBUG, + req.u.debug_exception.type, -1, + req.u.debug_exception.insn_length, + req.data.regs.x86.cr2); + if (rc < 0) + { + ERROR("Error %d injecting breakpoint\n", rc); + interrupted = -1; + continue; + } + + break; default: fprintf(stderr, "UNKNOWN REASON CODE %d\n", req.reason); } diff --git a/xen/arch/x86/hvm/monitor.c b/xen/arch/x86/hvm/monitor.c index 8b41b56..5e040ed 100644 --- a/xen/arch/x86/hvm/monitor.c +++ b/xen/arch/x86/hvm/monitor.c @@ -88,12 +88,14 @@ static inline unsigned long gfn_of_rip(unsigned long rip) return paging_gva_to_gfn(curr, sreg.base + rip, &pfec); } -int hvm_monitor_breakpoint(unsigned long rip, - enum hvm_monitor_breakpoint_type type) +int hvm_monitor_debug(unsigned long rip, enum hvm_monitor_debug_type type, + unsigned long trap_type, unsigned long insn_length) { struct vcpu *curr = current; struct arch_domain *ad = &curr->domain->arch; vm_event_request_t req = {}; + bool_t sync; + int rc; switch ( type ) { @@ -102,6 +104,9 @@ int hvm_monitor_breakpoint(unsigned long rip, return 0; req.reason = VM_EVENT_REASON_SOFTWARE_BREAKPOINT; req.u.software_breakpoint.gfn = gfn_of_rip(rip); + req.u.software_breakpoint.type = trap_type; + req.u.software_breakpoint.insn_length = insn_length; + sync = 1; break; case HVM_MONITOR_SINGLESTEP_BREAKPOINT: @@ -109,6 +114,17 @@ int hvm_monitor_breakpoint(unsigned long rip, return 0; req.reason = VM_EVENT_REASON_SINGLESTEP; req.u.singlestep.gfn = gfn_of_rip(rip); + sync = 1; + break; + + case HVM_MONITOR_DEBUG_EXCEPTION: + if ( !ad->monitor.debug_exception_enabled ) + return 0; + req.reason = VM_EVENT_REASON_DEBUG_EXCEPTION; + req.u.debug_exception.gfn = gfn_of_rip(rip); + req.u.debug_exception.type = trap_type; + req.u.debug_exception.insn_length = insn_length; + sync = !!ad->monitor.debug_exception_sync; break; default: @@ -117,7 +133,11 @@ int hvm_monitor_breakpoint(unsigned long rip, req.vcpu_id = curr->vcpu_id; - return vm_event_monitor_traps(curr, 1, &req); + rc = vm_event_monitor_traps(curr, sync, &req); + if ( type == HVM_MONITOR_DEBUG_EXCEPTION && rc == 1 && !sync ) + rc = 0; + + return rc; } /* diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index 081aef1..cea0761 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -3377,9 +3377,25 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs) HVMTRACE_1D(TRAP_DEBUG, exit_qualification); write_debugreg(6, exit_qualification | DR_STATUS_RESERVED_ONE); if ( !v->domain->debugger_attached ) - vmx_propagate_intr(intr_info); + { + unsigned long insn_length = 0; + int handled; + unsigned long trap_type = MASK_EXTR(intr_info, + INTR_INFO_INTR_TYPE_MASK); + + if( trap_type >= X86_EVENTTYPE_SW_INTERRUPT ) + __vmread(VM_EXIT_INSTRUCTION_LEN, &insn_length); + + handled = hvm_monitor_debug(regs->eip, + HVM_MONITOR_DEBUG_EXCEPTION, + trap_type, insn_length); + if ( handled <= 0 ) + vmx_propagate_intr(intr_info); + + } else domain_pause_for_debugger(); + break; case TRAP_int3: { @@ -3393,8 +3409,9 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs) } else { int handled = - hvm_monitor_breakpoint(regs->eip, - HVM_MONITOR_SOFTWARE_BREAKPOINT); + hvm_monitor_debug(regs->eip, + HVM_MONITOR_SOFTWARE_BREAKPOINT, + X86_EVENTTYPE_SW_EXCEPTION, 1); if ( handled < 0 ) { @@ -3721,8 +3738,7 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs) vmx_update_cpu_exec_control(v); if ( v->arch.hvm_vcpu.single_step ) { - hvm_monitor_breakpoint(regs->eip, - HVM_MONITOR_SINGLESTEP_BREAKPOINT); + hvm_monitor_debug(regs->eip, HVM_MONITOR_SINGLESTEP_BREAKPOINT, 0, 0); if ( v->domain->debugger_attached ) domain_pause_for_debugger(); } diff --git a/xen/arch/x86/monitor.c b/xen/arch/x86/monitor.c index 621f91a..e8b79f6 100644 --- a/xen/arch/x86/monitor.c +++ b/xen/arch/x86/monitor.c @@ -124,6 +124,22 @@ int arch_monitor_domctl_event(struct domain *d, break; } + case XEN_DOMCTL_MONITOR_EVENT_DEBUG_EXCEPTION: + { + bool_t old_status = ad->monitor.debug_exception_enabled; + + if ( unlikely(old_status == requested_status) ) + return -EEXIST; + + domain_pause(d); + ad->monitor.debug_exception_enabled = requested_status; + ad->monitor.debug_exception_sync = requested_status ? + mop->u.debug_exception.sync : + 0; + domain_unpause(d); + break; + } + default: /* * Should not be reached unless arch_monitor_get_capabilities() is diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h index 165e533..1cf97c3 100644 --- a/xen/include/asm-x86/domain.h +++ b/xen/include/asm-x86/domain.h @@ -405,6 +405,8 @@ struct arch_domain unsigned int mov_to_msr_extended : 1; unsigned int singlestep_enabled : 1; unsigned int software_breakpoint_enabled : 1; + unsigned int debug_exception_enabled : 1; + unsigned int debug_exception_sync : 1; } monitor; /* Mem_access emulation control */ diff --git a/xen/include/asm-x86/hvm/monitor.h b/xen/include/asm-x86/hvm/monitor.h index 55d435e..8b0f119 100644 --- a/xen/include/asm-x86/hvm/monitor.h +++ b/xen/include/asm-x86/hvm/monitor.h @@ -23,10 +23,11 @@ #include <xen/paging.h> #include <public/vm_event.h> -enum hvm_monitor_breakpoint_type +enum hvm_monitor_debug_type { HVM_MONITOR_SOFTWARE_BREAKPOINT, HVM_MONITOR_SINGLESTEP_BREAKPOINT, + HVM_MONITOR_DEBUG_EXCEPTION, }; /* @@ -39,8 +40,8 @@ bool_t hvm_monitor_cr(unsigned int index, unsigned long value, #define hvm_monitor_crX(cr, new, old) \ hvm_monitor_cr(VM_EVENT_X86_##cr, new, old) void hvm_monitor_msr(unsigned int msr, uint64_t value); -int hvm_monitor_breakpoint(unsigned long rip, - enum hvm_monitor_breakpoint_type type); +int hvm_monitor_debug(unsigned long rip, enum hvm_monitor_debug_type type, + unsigned long trap_type, unsigned long insn_length); #endif /* __ASM_X86_HVM_MONITOR_H__ */ diff --git a/xen/include/asm-x86/monitor.h b/xen/include/asm-x86/monitor.h index 0fee750..74a08f0f 100644 --- a/xen/include/asm-x86/monitor.h +++ b/xen/include/asm-x86/monitor.h @@ -74,7 +74,8 @@ static inline uint32_t arch_monitor_get_capabilities(struct domain *d) capabilities = (1U << XEN_DOMCTL_MONITOR_EVENT_WRITE_CTRLREG) | (1U << XEN_DOMCTL_MONITOR_EVENT_MOV_TO_MSR) | (1U << XEN_DOMCTL_MONITOR_EVENT_SOFTWARE_BREAKPOINT) | - (1U << XEN_DOMCTL_MONITOR_EVENT_GUEST_REQUEST); + (1U << XEN_DOMCTL_MONITOR_EVENT_GUEST_REQUEST) | + (1U << XEN_DOMCTL_MONITOR_EVENT_DEBUG_EXCEPTION); /* Since we know this is on VMX, we can just call the hvm func */ if ( hvm_is_singlestep_supported() ) diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h index 35adce2..b69b1bb 100644 --- a/xen/include/public/domctl.h +++ b/xen/include/public/domctl.h @@ -1081,6 +1081,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_psr_cmt_op_t); #define XEN_DOMCTL_MONITOR_EVENT_SOFTWARE_BREAKPOINT 3 #define XEN_DOMCTL_MONITOR_EVENT_GUEST_REQUEST 4 #define XEN_DOMCTL_MONITOR_EVENT_PRIVILEGED_CALL 5 +#define XEN_DOMCTL_MONITOR_EVENT_DEBUG_EXCEPTION 6 struct xen_domctl_monitor_op { uint32_t op; /* XEN_DOMCTL_MONITOR_OP_* */ @@ -1116,6 +1117,11 @@ struct xen_domctl_monitor_op { /* Pause vCPU until response */ uint8_t sync; } guest_request; + + struct { + /* Pause vCPU until response */ + uint8_t sync; + } debug_exception; } u; }; typedef struct xen_domctl_monitor_op xen_domctl_monitor_op_t; diff --git a/xen/include/public/vm_event.h b/xen/include/public/vm_event.h index 6ff7cc0..13855b5 100644 --- a/xen/include/public/vm_event.h +++ b/xen/include/public/vm_event.h @@ -29,7 +29,7 @@ #include "xen.h" -#define VM_EVENT_INTERFACE_VERSION 0x00000001 +#define VM_EVENT_INTERFACE_VERSION 0x00000002 #if defined(__XEN__) || defined(__XEN_TOOLS__) @@ -121,6 +121,8 @@ #define VM_EVENT_REASON_GUEST_REQUEST 8 /* Privileged call executed (e.g. SMC) */ #define VM_EVENT_REASON_PRIVILEGED_CALL 9 +/* A debug exception was caught */ +#define VM_EVENT_REASON_DEBUG_EXCEPTION 10 /* Supported values for the vm_event_write_ctrlreg index. */ #define VM_EVENT_X86_CR0 0 @@ -258,8 +260,15 @@ struct vm_event_write_ctrlreg { uint64_t old_value; }; +struct vm_event_singlestep { + uint64_t gfn; +}; + struct vm_event_debug { uint64_t gfn; + uint8_t type; /* HVMOP_TRAP_* */ + uint8_t insn_length; + uint8_t _pad[6]; }; struct vm_event_mov_to_msr { @@ -303,7 +312,8 @@ typedef struct vm_event_st { struct vm_event_write_ctrlreg write_ctrlreg; struct vm_event_mov_to_msr mov_to_msr; struct vm_event_debug software_breakpoint; - struct vm_event_debug singlestep; + struct vm_event_singlestep singlestep; + struct vm_event_debug debug_exception; } u; union {

[v4,8/8] x86/vm_event: Add HVM debug exception vm_events

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