The following commit has been merged into the efi/urgent branch of tip: Commit-ID: a470552ee8965da0fe6fd4df0aa39c4cda652c7c Gitweb: https://git.kernel.org/tip/a470552ee8965da0fe6fd4df0aa39c4cda652c7c Author: Ard Biesheuvel <ardb@xxxxxxxxxx> AuthorDate: Tue, 10 Dec 2019 10:09:45 +01:00 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitterDate: Tue, 10 Dec 2019 12:13:02 +01:00 efi: Don't attempt to map RCI2 config table if it doesn't exist Commit: 1c5fecb61255aa12 ("efi: Export Runtime Configuration Interface table to sysfs") ... added support for a Dell specific UEFI configuration table, but failed to take into account that mapping the table should not be attempted unless the table actually exists. If it doesn't exist, the code usually fails silently unless pr_debug() prints are enabled. However, on 32-bit PAE x86, the splat below is produced due to the attempt to map the placeholder value EFI_INVALID_TABLE_ADDR which we use for non-existing UEFI configuration tables, and which equals ULONG_MAX. memremap attempted on mixed range 0x00000000ffffffff size: 0x1e WARNING: CPU: 1 PID: 1 at kernel/iomem.c:81 memremap+0x1a3/0x1c0 Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.4.2-smp-mine #1 Hardware name: Hewlett-Packard HP Z400 Workstation/0B4Ch, BIOS 786G3 v03.61 03/05/2018 EIP: memremap+0x1a3/0x1c0 ... Call Trace: ? map_properties+0x473/0x473 ? efi_rci2_sysfs_init+0x2c/0x154 ? map_properties+0x473/0x473 ? do_one_initcall+0x49/0x1d4 ? parse_args+0x1e8/0x2a0 ? do_early_param+0x7a/0x7a ? kernel_init_freeable+0x139/0x1c2 ? rest_init+0x8e/0x8e ? kernel_init+0xd/0xf2 ? ret_from_fork+0x2e/0x38 Fix this by checking whether the table exists before attempting to map it. Reported-by: Richard Narron <comet.berkeley@xxxxxxxxx> Tested-by: Richard Narron <comet.berkeley@xxxxxxxxx> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Cc: linux-efi@xxxxxxxxxxxxxxx Fixes: 1c5fecb61255aa12 ("efi: Export Runtime Configuration Interface table to sysfs") Link: https://lkml.kernel.org/r/20191210090945.11501-2-ardb@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- drivers/firmware/efi/rci2-table.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/firmware/efi/rci2-table.c b/drivers/firmware/efi/rci2-table.c index 76b0c35..de1a9a1 100644 --- a/drivers/firmware/efi/rci2-table.c +++ b/drivers/firmware/efi/rci2-table.c @@ -81,6 +81,9 @@ static int __init efi_rci2_sysfs_init(void) struct kobject *tables_kobj; int ret = -ENOMEM; + if (rci2_table_phys == EFI_INVALID_TABLE_ADDR) + return 0; + rci2_base = memremap(rci2_table_phys, sizeof(struct rci2_table_global_hdr), MEMREMAP_WB);
