Merge tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 TDX updates from Dave Hansen:
 "This contains the initial support for host-side TDX support so that
  KVM can run TDX-protected guests. This does not include the actual
  KVM-side support which will come from the KVM folks. The TDX host
  interactions with kexec also needs to be ironed out before this is
  ready for prime time, so this code is currently Kconfig'd off when
  kexec is on.

  The majority of the code here is the kernel telling the TDX module
  which memory to protect and handing some additional memory over to it
  to use to store TDX module metadata. That sounds pretty simple, but
  the TDX architecture is rather flexible and it takes quite a bit of
  back-and-forth to say, "just protect all memory, please."

  There is also some code tacked on near the end of the series to handle
  a hardware erratum. The erratum can make software bugs such as a
  kernel write to TDX-protected memory cause a machine check and
  masquerade as a real hardware failure. The erratum handling watches
  out for these and tries to provide nicer user errors"

* tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/virt/tdx: Make TDX host depend on X86_MCE
  x86/virt/tdx: Disable TDX host support when kexec is enabled
  Documentation/x86: Add documentation for TDX host support
  x86/mce: Differentiate real hardware #MCs from TDX erratum ones
  x86/cpu: Detect TDX partial write machine check erratum
  x86/virt/tdx: Handle TDX interaction with sleep and hibernation
  x86/virt/tdx: Initialize all TDMRs
  x86/virt/tdx: Configure global KeyID on all packages
  x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID
  x86/virt/tdx: Designate reserved areas for all TDMRs
  x86/virt/tdx: Allocate and set up PAMTs for TDMRs
  x86/virt/tdx: Fill out TDMRs to cover all TDX memory regions
  x86/virt/tdx: Add placeholder to construct TDMRs to cover all TDX memory regions
  x86/virt/tdx: Get module global metadata for module initialization
  x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory
  x86/virt/tdx: Add skeleton to enable TDX on demand
  x86/virt/tdx: Add SEAMCALL error printing for module initialization
  x86/virt/tdx: Handle SEAMCALL no entropy error in common code
  x86/virt/tdx: Make INTEL_TDX_HOST depend on X86_X2APIC
  x86/virt/tdx: Define TDX supported page sizes as macros
  ...

1 files changed, 16 insertions, 1 deletions

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index fd5ce12c4f9a..bc39252bc54f 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -53,6 +53,7 @@
 #include <asm/mce.h>
 #include <asm/msr.h>
 #include <asm/reboot.h>
+#include <asm/tdx.h>
 
 #include "internal.h"
 
@@ -229,12 +230,20 @@ static void wait_for_panic(void)
 	panic("Panicing machine check CPU died");
 }
 
+static const char *mce_dump_aux_info(struct mce *m)
+{
+	if (boot_cpu_has_bug(X86_BUG_TDX_PW_MCE))
+		return tdx_dump_mce_info(m);
+
+	return NULL;
+}
+
 static noinstr void mce_panic(const char *msg, struct mce *final, char *exp)
 {
 	struct llist_node *pending;
 	struct mce_evt_llist *l;
 	int apei_err = 0;
-	struct page *p;
+	const char *memmsg;
 
 	/*
 	 * Allow instrumentation around external facilities usage. Not that it
@@ -285,6 +294,11 @@ static noinstr void mce_panic(const char *msg, struct mce *final, char *exp)
 	}
 	if (exp)
 		pr_emerg(HW_ERR "Machine check: %s\n", exp);
+
+	memmsg = mce_dump_aux_info(final);
+	if (memmsg)
+		pr_emerg(HW_ERR "Machine check: %s\n", memmsg);
+
 	if (!fake_panic) {
 		if (panic_timeout == 0)
 			panic_timeout = mca_cfg.panic_timeout;
@@ -297,6 +311,7 @@ static noinstr void mce_panic(const char *msg, struct mce *final, char *exp)
 		 */
 		if (kexec_crash_loaded()) {
 			if (final && (final->status & MCI_STATUS_ADDRV)) {
+				struct page *p;
 				p = pfn_to_online_page(final->addr >> PAGE_SHIFT);
 				if (p)
 					SetPageHWPoison(p);