On Mon, Sep 25, 2023 at 01:58:18PM +0800, Michael Chang via Grub-devel wrote: > During attempts to configure a serial console, a Page Fault Exception > and system reset were encountered, specifically on release 2.12-rc1. > This issue was not present in prior versions and seemed to affect only a > specific machine, potentially pointing to hardware or firmware flaw. > > After investigation, it was discovered that the invalid page access > occurred during the discovery of serial MMIO ports as specified by > ACPI's SPCR table [1]. The recent change uncovered an issue in Grub's > ACPI driver. > > In certain cases, the XSDT/RSDT root table might contain a null entry as > a terminator, depending on how the tables are assembled. Grub cannot > blindly trust the address in the root table to be valid and should > perform a sanity check for null entries. This patch introduces this > simple check. > > This fix is also inspired by a related Linux kernel fix [2]: > > [1] 7b192ec4c term/ns8250: Use ACPI SPCR table when available to configure > serial > [2] 0f929fbf0 ACPICA: Tables: Add new mechanism to skip NULL entries in RSDT > and XSDT. > > Signed-off-by: Michael Chang <mch...@suse.com>
Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> Daniel _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
