x86/purgatory: Disable the stackleak GCC plugin for the purgatory
Since commit:
b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS")
kexec breaks if GCC_PLUGIN_STACKLEAK=y is enabled, as the purgatory
contains undefined references to stackleak_track_stack.
Attempting to load a kexec kernel results in this failure:
kexec: Undefined symbol: stackleak_track_stack
kexec-bzImage64: Loading purgatory failed
Fix this by disabling the stackleak plugin for the purgatory.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes:
b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS")
Link: https://lkml.kernel.org/r/20190923171753.GA2252517@rani.riverdale.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>