Fix the panic where KEXEC'd kernel does not have access to EFI runtime mappings. This may cause the extended UVsystab to not be available. The solution is to revert to non-UV mode and continue with limited capabilities. Signed-off-by: Mike Travis Acked-by: Dimitri Sivanich Reviewed-by: Russ Anderson Reviewed-by: Alex Thorlton --- arch/x86/kernel/apic/x2apic_uv_x.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) --- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c +++ linux/arch/x86/kernel/apic/x2apic_uv_x.c @@ -1172,19 +1172,25 @@ static void __init decode_gam_rng_tbl(un index, _min_socket, _max_socket, _min_pnode, _max_pnode); } -static void __init decode_uv_systab(void) +static int __init decode_uv_systab(void) { struct uv_systab *st; int i; + if (uv_hub_info->hub_revision < UV4_HUB_REVISION_BASE) + return 0; /* No extended UVsystab required */ + st = uv_systab; - if ((!st || st->revision < UV_SYSTAB_VERSION_UV4) && !is_uv4_hub()) - return; - if (st->revision != UV_SYSTAB_VERSION_UV4_LATEST) { - pr_crit( + if ((!st) || (st->revision < UV_SYSTAB_VERSION_UV4_LATEST)) { + int rev = st ? st->revision : 0; + + pr_err( "UV: BIOS UVsystab version(%x) mismatch, expecting(%x)\n", - st->revision, UV_SYSTAB_VERSION_UV4_LATEST); - BUG(); + rev, UV_SYSTAB_VERSION_UV4_LATEST); + pr_err( + "UV: Cannot support UV operations, switching to generic PC\n"); + uv_system_type = UV_NONE; + return -EINVAL; } for (i = 0; st->entry[i].type != UV_SYSTAB_TYPE_UNUSED; i++) { @@ -1205,6 +1211,7 @@ static void __init decode_uv_systab(void break; } } + return 0; } /* @@ -1373,7 +1380,8 @@ void __init uv_system_init(void) map_low_mmrs(); uv_bios_init(); /* get uv_systab for decoding */ - decode_uv_systab(); + if (decode_uv_systab() < 0) + return; /* UVsystab problem, abort UV init */ build_socket_tables(); build_uv_gr_table(); uv_init_hub_info(&hub_info); --