This is a RESEND post. The original v1 post can be found here: http://lkml.kernel.org/r/20180829141624.13985-1-...@redhat.com
It's trying to fix several corner case issues for kexec/kdump when dynamic switching of paging mode is enabled in x86_64. Please click above link to check the details. In v1, hpa raised concern that why the paging mode checking is not done before kexec jumping, the discussion can be found here: http://lkml.kernel.org/r/alpine.deb.2.21.1809051002020.1...@nanos.tec.linutronix.de As tglx said, it might be not doable for kdump since kdump kernel's reserved crashkernel region only owns a portion of memory, may be above 4G; and might be not safer to do paging mode checking and switching thing after crash. So resend this patchset. Baoquan He (3): x86/boot: Add bit fields into xloadflags for 5-level kernel checking x86/kexec/64: Error out if try to jump to old 4-level kernel from 5-level kernel x86/kdump/64: Change the upper limit of crashkernel reservation arch/x86/boot/header.S | 12 +++++++++++- arch/x86/include/uapi/asm/bootparam.h | 2 ++ arch/x86/kernel/kexec-bzimage64.c | 5 +++++ arch/x86/kernel/setup.c | 18 ++++++++++++++---- 4 files changed, 32 insertions(+), 5 deletions(-) -- 2.13.6
