x86, mm: Fix CONFIG_VMSPLIT_1G and 2G_OPT trampoline

commit b7d460897739e02f186425b7276e3fdb1595cea7 upstream.

rc2 kernel crashes when booting second cpu on this CONFIG_VMSPLIT_2G_OPT
laptop: whereas cloning from kernel to low mappings pgd range does need
to limit by both KERNEL_PGD_PTRS and KERNEL_PGD_BOUNDARY, cloning kernel
pgd range itself must not be limited by the smaller KERNEL_PGD_BOUNDARY.

Signed-off-by: Hugh Dickins <hughd@google.com>
LKML-Reference: <alpine.LSU.2.00.1008242235120.2515@sister.anvils>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/x86/kernel/trampoline.c b/arch/x86/kernel/trampoline.c
index 4e816a488cf1e59088d6f8156edd14b531d96332..0ac23a7bf6f162edd191e53c61fe2b0cf1da3a17 100644 (file)
--- a/arch/x86/kernel/trampoline.c
+++ b/arch/x86/kernel/trampoline.c
@@ -47,8 +47,7 @@ void __init setup_trampoline_page_table(void)
        /* Copy kernel address range */
        clone_pgd_range(trampoline_pg_dir + KERNEL_PGD_BOUNDARY,
                        swapper_pg_dir + KERNEL_PGD_BOUNDARY,
-                       min_t(unsigned long, KERNEL_PGD_PTRS,
-                             KERNEL_PGD_BOUNDARY));
+                       KERNEL_PGD_PTRS);
 
        /* Initialize low mappings */
        clone_pgd_range(trampoline_pg_dir,