x86/sev-es: Handle #DB Events (cb1ad3ec) · Commits · 戴 / test

Handle #VC exceptions caused by #DB exceptions in the guest. Those must be handled outside of instrumentation_begin()/end() so that the handler will not be raised recursively. Handle them by calling the kernel's debug exception handler. Signed-off-by:

Joerg Roedel <jroedel@suse.de> Signed-off-by:

Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200907131613.12703-62-joro@8bytes.org

arch/x86/kernel/sev-es.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -922,6 +922,14 @@ static enum es_result vc_handle_trap_ac(struct ghcb *ghcb,
		return ES_EXCEPTION;
		}

		static __always_inline void vc_handle_trap_db(struct pt_regs *regs)
		{
		if (user_mode(regs))
		noist_exc_debug(regs);
		else
		exc_debug(regs);
		}

		static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
		struct ghcb *ghcb,
		unsigned long exit_code)
		@@ -1033,6 +1041,15 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
		struct ghcb *ghcb;

		lockdep_assert_irqs_disabled();

		/*
		* Handle #DB before calling into !noinstr code to avoid recursive #DB.
		*/
		if (error_code == SVM_EXIT_EXCP_BASE + X86_TRAP_DB) {
		vc_handle_trap_db(regs);
		return;
		}

		instrumentation_begin();

		/*

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