[xen staging] x86/traps: Clean up diagnostics

[patchbot@xxxxxxx]

commit 8e3edefb880caeeaaf80123d5599139e8c2c9ecf
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Fri Oct 8 13:40:17 2021 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Fri Dec 17 17:03:54 2021 +0000

    x86/traps: Clean up diagnostics
    
    do{_unhandled,}_trap() should use fatal_trap() rather than opencoding part 
of
    it.  This lets the remote stack trace logic work in more fatal error
    conditions.
    
    With do_trap() converted, there is only one single user of trapstr()
    remaining.  Tweak the formatting in pv_inject_event(), and remove trapstr()
    entirely.  Rename vec_name() to vector_name() now that it is exported.
    
    Take the opportunity of vector_name() being exported to improve the
    diagnostics in stub_selftest().
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/extable.c           |  8 +++++---
 xen/arch/x86/include/asm/traps.h |  2 +-
 xen/arch/x86/pv/traps.c          |  6 +++---
 xen/arch/x86/traps.c             | 29 +++++------------------------
 4 files changed, 14 insertions(+), 31 deletions(-)

diff --git a/xen/arch/x86/extable.c b/xen/arch/x86/extable.c
index 109ab7da98..78d6727225 100644
--- a/xen/arch/x86/extable.c
+++ b/xen/arch/x86/extable.c
@@ -124,6 +124,8 @@ search_exception_table(const struct cpu_user_regs *regs)
 }
 
 #ifndef NDEBUG
+#include <asm/traps.h>
+
 static int __init stub_selftest(void)
 {
     static const struct {
@@ -172,10 +174,10 @@ static int __init stub_selftest(void)
         if ( res.raw != tests[i].res.raw )
         {
             printk("Selftest %u failed: Opc %*ph "
-                   "expected %u[%04x], got %u[%04x]\n",
+                   "expected %s[%04x], got %s[%04x]\n",
                    i, (int)ARRAY_SIZE(tests[i].opc), tests[i].opc,
-                   tests[i].res.fields.trapnr, tests[i].res.fields.ec,
-                   res.fields.trapnr, res.fields.ec);
+                   vector_name(tests[i].res.fields.trapnr), 
tests[i].res.fields.ec,
+                   vector_name(res.fields.trapnr), res.fields.ec);
 
             fail = true;
         }
diff --git a/xen/arch/x86/include/asm/traps.h b/xen/arch/x86/include/asm/traps.h
index ec23d3a70b..b0dd2d2461 100644
--- a/xen/arch/x86/include/asm/traps.h
+++ b/xen/arch/x86/include/asm/traps.h
@@ -19,7 +19,7 @@
 #ifndef ASM_TRAP_H
 #define ASM_TRAP_H
 
-const char *trapstr(unsigned int trapnr);
+const char *vector_name(unsigned int vec);
 
 #endif /* ASM_TRAP_H */
 
diff --git a/xen/arch/x86/pv/traps.c b/xen/arch/x86/pv/traps.c
index 1e05a9f1cd..170e103098 100644
--- a/xen/arch/x86/pv/traps.c
+++ b/xen/arch/x86/pv/traps.c
@@ -89,9 +89,9 @@ void pv_inject_event(const struct x86_event *event)
 
     if ( unlikely(null_trap_bounce(curr, tb)) )
     {
-        gprintk(XENLOG_WARNING,
-                "Unhandled %s fault/trap [#%d, ec=%04x]\n",
-                trapstr(vector), vector, error_code);
+        gprintk(XENLOG_ERR,
+                "Unhandled: vec %u, %s[%04x]\n",
+                vector, vector_name(vector), error_code);
 
         if ( vector == TRAP_page_fault )
             show_page_walk(event->cr2);
diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 581d8be2aa..485bd66971 100644
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -767,21 +767,7 @@ static int nmi_show_execution_state(const struct 
cpu_user_regs *regs, int cpu)
     return 1;
 }
 
-const char *trapstr(unsigned int trapnr)
-{
-    static const char * const strings[] = {
-        "divide error", "debug", "nmi", "bkpt", "overflow", "bounds",
-        "invalid opcode", "device not available", "double fault",
-        "coprocessor segment", "invalid tss", "segment not found",
-        "stack error", "general protection fault", "page fault",
-        "spurious interrupt", "coprocessor error", "alignment check",
-        "machine check", "simd error", "virtualisation exception"
-    };
-
-    return trapnr < ARRAY_SIZE(strings) ? strings[trapnr] : "???";
-}
-
-static const char *vec_name(unsigned int vec)
+const char *vector_name(unsigned int vec)
 {
     static const char names[][4] = {
 #define P(x) [X86_EXC_ ## x] = "#" #x
@@ -855,7 +841,7 @@ void fatal_trap(const struct cpu_user_regs *regs, bool 
show_remote)
     }
 
     panic("FATAL TRAP: vec %u, %s[%04x]%s\n",
-          trapnr, vec_name(trapnr), regs->error_code,
+          trapnr, vector_name(trapnr), regs->error_code,
           (regs->eflags & X86_EFLAGS_IF) ? "" : " IN INTERRUPT CONTEXT");
 }
 
@@ -866,9 +852,7 @@ void do_unhandled_trap(struct cpu_user_regs *regs)
     if ( debugger_trap_fatal(trapnr, regs) )
         return;
 
-    show_execution_state(regs);
-    panic("FATAL RESERVED TRAP: vec %u, %s[%04x]\n",
-          trapnr, vec_name(trapnr), regs->error_code);
+    fatal_trap(regs, false);
 }
 
 static void fixup_exception_return(struct cpu_user_regs *regs,
@@ -942,7 +926,7 @@ static bool extable_fixup(struct cpu_user_regs *regs, bool 
print)
      */
     if ( IS_ENABLED(CONFIG_DEBUG) && print )
         printk(XENLOG_GUEST XENLOG_WARNING "Fixup %s[%04x]: %p [%ps] -> %p\n",
-               vec_name(regs->entry_vector), regs->error_code,
+               vector_name(regs->entry_vector), regs->error_code,
                _p(regs->rip), _p(regs->rip), _p(fixup));
 
     fixup_exception_return(regs, fixup);
@@ -978,10 +962,7 @@ void do_trap(struct cpu_user_regs *regs)
     if ( debugger_trap_fatal(trapnr, regs) )
         return;
 
-    show_execution_state(regs);
-    panic("FATAL TRAP: vector = %d (%s)\n"
-          "[error_code=%04x]\n",
-          trapnr, trapstr(trapnr), regs->error_code);
+    fatal_trap(regs, false);
 }
 
 int guest_rdmsr_xen(const struct vcpu *v, uint32_t idx, uint64_t *val)
--
generated by git-patchbot for /home/xen/git/xen.git#staging