From 42b3a4cb5609de757f5445fcad18945ba9239a07 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 24 Nov 2017 09:42:21 +0100 Subject: x86/xen: Support early interrupts in xen pv guests Add early interrupt handlers activated by idt_setup_early_handler() to the handlers supported by Xen pv guests. This will allow for early WARN() calls not crashing the guest. Suggested-by: Andy Lutomirski Signed-off-by: Juergen Gross Signed-off-by: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: https://lkml.kernel.org/r/20171124084221.30172-1-jgross@suse.com --- arch/x86/include/asm/segment.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'arch/x86/include/asm/segment.h') diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index b20f9d623f9c..8f09012b92e7 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -236,11 +236,23 @@ */ #define EARLY_IDT_HANDLER_SIZE 9 +/* + * xen_early_idt_handler_array is for Xen pv guests: for each entry in + * early_idt_handler_array it contains a prequel in the form of + * pop %rcx; pop %r11; jmp early_idt_handler_array[i]; summing up to + * max 8 bytes. + */ +#define XEN_EARLY_IDT_HANDLER_SIZE 8 + #ifndef __ASSEMBLY__ extern const char early_idt_handler_array[NUM_EXCEPTION_VECTORS][EARLY_IDT_HANDLER_SIZE]; extern void early_ignore_irq(void); +#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV) +extern const char xen_early_idt_handler_array[NUM_EXCEPTION_VECTORS][XEN_EARLY_IDT_HANDLER_SIZE]; +#endif + /* * Load a segment. Fall back on loading the zero segment if something goes * wrong. This variant assumes that loading zero fully clears the segment. -- cgit v1.2.3