From 6c932a788cdca15494e1c9d06c7befacf1583a2a Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Mon, 1 Nov 2021 10:19:57 +0000 Subject: [PATCH] x86/setup: Read CR4 earlier in __start_xen() This is necessary for read_cr4() to function correctly. Move the EFER caching at the same time. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich (cherry picked from commit 9851bc4939101828d2ad7634b93c0d9ccaef5b7e) --- xen/arch/x86/setup.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c index d5274f8c21..297845d691 100644 --- a/xen/arch/x86/setup.c +++ b/xen/arch/x86/setup.c @@ -851,6 +851,9 @@ void __init noreturn __start_xen(unsigned long mbi_p) /* Full exception support from here on in. */ + rdmsrl(MSR_EFER, this_cpu(efer)); + asm volatile ( "mov %%cr4,%0" : "=r" (get_cpu_info()->cr4) ); + /* Enable NMIs. Our loader (e.g. Tboot) may have left them disabled. */ enable_nmis(); @@ -897,9 +900,6 @@ void __init noreturn __start_xen(unsigned long mbi_p) parse_video_info(); - rdmsrl(MSR_EFER, this_cpu(efer)); - asm volatile ( "mov %%cr4,%0" : "=r" (get_cpu_info()->cr4) ); - /* We initialise the serial devices very early so we can get debugging. */ ns16550.io_base = 0x3f8; ns16550.irq = 4; -- 2.39.5