arm64: Mark kernel as tainted on SAE and SError panic

Set TAINT_MACHINE_CHECK when SError or Synchronous External Abort (SEA)
interrupts trigger a panic to flag potential hardware faults. This
tainting mechanism aids in debugging and enables correlation of
hardware-related crashes in large-scale deployments.

This change aligns with similar patches[1] that mark machine check
events when the system crashes due to hardware errors.

Link: https://lore.kernel.org/all/[email protected]/ [1]
Signed-off-by: Breno Leitao <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

Author: leitao

arch/arm64/kernel/traps.c

@@ -931,6 +931,7 @@ void __noreturn panic_bad_stack(struct pt_regs *regs, unsigned long esr, unsigne
 
 void __noreturn arm64_serror_panic(struct pt_regs *regs, unsigned long esr)
 {
+	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_STILL_OK);
 	console_verbose();
 
 	pr_crit("SError Interrupt on CPU%d, code 0x%016lx -- %s\n",

arch/arm64/mm/fault.c

@@ -826,6 +826,7 @@ static int do_sea(unsigned long far, unsigned long esr, struct pt_regs *regs)
 		 */
 		siaddr  = untagged_addr(far);
 	}
+	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_STILL_OK);
 	arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
 
 	return 0;