On Mon, Mar 18, 2024 at 07:02:45AM +0000, Ashish Kalra wrote: > From: Ashish Kalra <ashish.kalra@xxxxxxx> > > During crashkernel boot only pre-allocated crash memory is presented as > E820_TYPE_RAM. This can cause page table entries mapping unaccepted memory > table to be zapped during phys_pte_init(), phys_pmd_init(), phys_pud_init() > and phys_p4d_init() as SNP/TDX guest use E820_TYPE_ACPI to store the > unaccepted memory table and pass it between the kernels on > kexec/kdump. > > E820_TYPE_ACPI covers not only ACPI data, but also EFI tables and might > be required by kernel to function properly. > > The problem was discovered during debugging kdump for SNP guest. The > unaccepted memory table stored with E820_TYPE_ACPI and passed between > the kernels on kdump was getting zapped as the PMD entry mapping this > is above the E820_TYPE_RAM range for the reserved crashkernel memory. > > Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> I guess it would be better if I take this patch into my kexec patchset. I guess I just got lucky not to step onto the issue. -- Kiryl Shutsemau / Kirill A. Shutemov _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
