Debugger support in the hypervisor is rarely used and it is opening a
way for dom0 to modify the running hypervisor by very easy means.
Add a Kconfig option to control support of gdbsx. Default is off.
Signed-off-by: Juergen Gross
---
xen/Kconfig.debug | 4
xen/arch/x86/Kconfig | 1 -
xen/arch/x86/domctl.c | 4
xen/common/Kconfig | 3 ---
xen/common/domain.c| 2 +-
xen/include/asm-x86/debugger.h | 30 ++
xen/include/xen/sched.h| 4
7 files changed, 31 insertions(+), 17 deletions(-)
diff --git a/xen/Kconfig.debug b/xen/Kconfig.debug
index 22573e74db..84a6e1b8eb 100644
--- a/xen/Kconfig.debug
+++ b/xen/Kconfig.debug
@@ -13,9 +13,13 @@ config DEBUG
if DEBUG || EXPERT = "y"
+config GDBSX
+ bool
+
config CRASH_DEBUG
bool "Crash Debugging Support"
depends on X86
+ select GDBSX
---help---
If you want to attach gdb to Xen to debug Xen if it crashes
then say Y.
diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
index 28b3b4692a..c72da8964a 100644
--- a/xen/arch/x86/Kconfig
+++ b/xen/arch/x86/Kconfig
@@ -13,7 +13,6 @@ config X86
select HAS_EHCI
select HAS_EX_TABLE
select HAS_FAST_MULTIPLY
- select HAS_GDBSX
select HAS_IOPORTS
select HAS_KEXEC
select MEM_ACCESS_ALWAYS_ON
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index 43e368d63b..90e36b9ad8 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -36,6 +36,7 @@
#include
#include
+#ifdef CONFIG_GDBSX
static int gdbsx_guest_mem_io(domid_t domid, struct xen_domctl_gdbsx_memio
*iop)
{
void * __user gva = (void *)iop->gva, * __user uva = (void *)iop->uva;
@@ -45,6 +46,7 @@ static int gdbsx_guest_mem_io(domid_t domid, struct
xen_domctl_gdbsx_memio *iop)
return iop->remain ? -EFAULT : 0;
}
+#endif
static void domain_cpu_policy_changed(struct domain *d)
{
@@ -912,6 +914,7 @@ long arch_do_domctl(
}
#endif
+#ifdef CONFIG_GDBSX
case XEN_DOMCTL_gdbsx_guestmemio:
domctl->u.gdbsx_guest_memio.remain = domctl->u.gdbsx_guest_memio.len;
ret = gdbsx_guest_mem_io(domctl->domain, >u.gdbsx_guest_memio);
@@ -976,6 +979,7 @@ long arch_do_domctl(
copyback = true;
break;
}
+#endif
case XEN_DOMCTL_setvcpuextstate:
case XEN_DOMCTL_getvcpuextstate:
diff --git a/xen/common/Kconfig b/xen/common/Kconfig
index f754741972..7bde6aff02 100644
--- a/xen/common/Kconfig
+++ b/xen/common/Kconfig
@@ -57,9 +57,6 @@ config HAS_UBSAN
config HAS_KEXEC
bool
-config HAS_GDBSX
- bool
-
config HAS_IOPORTS
bool
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 66c7fc..b4e041ffd0 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -915,7 +915,7 @@ void vcpu_end_shutdown_deferral(struct vcpu *v)
vcpu_check_shutdown(v);
}
-#ifdef CONFIG_HAS_GDBSX
+#ifdef CONFIG_GDBSX
void domain_pause_for_debugger(void)
{
struct vcpu *curr = current;
diff --git a/xen/include/asm-x86/debugger.h b/xen/include/asm-x86/debugger.h
index b1b627f1fa..4a8f226b86 100644
--- a/xen/include/asm-x86/debugger.h
+++ b/xen/include/asm-x86/debugger.h
@@ -47,18 +47,6 @@ static inline bool debugger_trap_fatal(
/* Int3 is a trivial way to gather cpu_user_regs context. */
#define debugger_trap_immediate() __asm__ __volatile__ ( "int3" );
-#else
-
-static inline bool debugger_trap_fatal(
-unsigned int vector, struct cpu_user_regs *regs)
-{
-return false;
-}
-
-#define debugger_trap_immediate() ((void)0)
-
-#endif
-
static inline bool debugger_trap_entry(
unsigned int vector, struct cpu_user_regs *regs)
{
@@ -88,4 +76,22 @@ unsigned int dbg_rw_mem(void * __user addr, void * __user
buf,
unsigned int len, domid_t domid, bool toaddr,
uint64_t pgd3);
+#else
+
+static inline bool debugger_trap_fatal(
+unsigned int vector, struct cpu_user_regs *regs)
+{
+return false;
+}
+
+#define debugger_trap_immediate() ((void)0)
+
+static inline bool debugger_trap_entry(
+unsigned int vector, struct cpu_user_regs *regs)
+{
+return false;
+}
+
+#endif
+
#endif /* __X86_DEBUGGER_H__ */
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 9f7bc69293..094003f562 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -652,7 +652,11 @@ void domain_destroy(struct domain *d);
int domain_kill(struct domain *d);
int domain_shutdown(struct domain *d, u8 reason);
void domain_resume(struct domain *d);
+#ifdef CONFIG_GDBSX
void domain_pause_for_debugger(void);
+#else
+static inline void domain_pause_for_debugger(void) { }
+#endif
int domain_soft_reset(struct domain *d);
--
2.16.4
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