The following commit has been merged into the x86/tdx branch of tip:
Commit-ID: 775acc82a88fd36f5e89a08d39874fdeeaa04247
Gitweb: https://git.kernel.org/tip/775acc82a88fd36f5e89a08d39874fdeeaa04247
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
AuthorDate: Wed, 06 Apr 2022 02:29:15 +03:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Thu, 07 Apr 2022 08:27:51 -07:00
x86/traps: Refactor exc_general_protection()
TDX brings a new exception -- Virtualization Exception (#VE). Handling
of #VE structurally very similar to handling #GP.
Extract two helpers from exc_general_protection() that can be reused for
handling #VE.
No functional changes.
Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20220405232939.73860-7-kirill.shutemov@xxxxxxxxxxxxxxx
---
arch/x86/kernel/traps.c | 57 +++++++++++++++++++++-------------------
1 file changed, 31 insertions(+), 26 deletions(-)
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 1563fb9..db8d22a 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -686,13 +686,40 @@ static bool try_fixup_enqcmd_gp(void)
#endif
}
+static bool gp_try_fixup_and_notify(struct pt_regs *regs, int trapnr,
+ unsigned long error_code, const char *str)
+{
+ if (fixup_exception(regs, trapnr, error_code, 0))
+ return true;
+
+ current->thread.error_code = error_code;
+ current->thread.trap_nr = trapnr;
+
+ /*
+ * To be potentially processing a kprobe fault and to trust the result
+ * from kprobe_running(), we have to be non-preemptible.
+ */
+ if (!preemptible() && kprobe_running() &&
+ kprobe_fault_handler(regs, trapnr))
+ return true;
+
+ return notify_die(DIE_GPF, str, regs, error_code, trapnr, SIGSEGV) == NOTIFY_STOP;
+}
+
+static void gp_user_force_sig_segv(struct pt_regs *regs, int trapnr,
+ unsigned long error_code, const char *str)
+{
+ current->thread.error_code = error_code;
+ current->thread.trap_nr = trapnr;
+ show_signal(current, SIGSEGV, "", str, regs, error_code);
+ force_sig(SIGSEGV);
+}
+
DEFINE_IDTENTRY_ERRORCODE(exc_general_protection)
{
char desc[sizeof(GPFSTR) + 50 + 2*sizeof(unsigned long) + 1] = GPFSTR;
enum kernel_gp_hint hint = GP_NO_HINT;
- struct task_struct *tsk;
unsigned long gp_addr;
- int ret;
if (user_mode(regs) && try_fixup_enqcmd_gp())
return;
@@ -711,40 +738,18 @@ DEFINE_IDTENTRY_ERRORCODE(exc_general_protection)
return;
}
- tsk = current;
-
if (user_mode(regs)) {
if (fixup_iopl_exception(regs))
goto exit;
- tsk->thread.error_code = error_code;
- tsk->thread.trap_nr = X86_TRAP_GP;
-
if (fixup_vdso_exception(regs, X86_TRAP_GP, error_code, 0))
goto exit;
- show_signal(tsk, SIGSEGV, "", desc, regs, error_code);
- force_sig(SIGSEGV);
+ gp_user_force_sig_segv(regs, X86_TRAP_GP, error_code, desc);
goto exit;
}
- if (fixup_exception(regs, X86_TRAP_GP, error_code, 0))
- goto exit;
-
- tsk->thread.error_code = error_code;
- tsk->thread.trap_nr = X86_TRAP_GP;
-
- /*
- * To be potentially processing a kprobe fault and to trust the result
- * from kprobe_running(), we have to be non-preemptible.
- */
- if (!preemptible() &&
- kprobe_running() &&
- kprobe_fault_handler(regs, X86_TRAP_GP))
- goto exit;
-
- ret = notify_die(DIE_GPF, desc, regs, error_code, X86_TRAP_GP, SIGSEGV);
- if (ret == NOTIFY_STOP)
+ if (gp_try_fixup_and_notify(regs, X86_TRAP_GP, error_code, desc))
goto exit;
if (error_code)
|