A UV4 chassis with only 2 sockets configured can unexpectedly target the wrong UV hub. Fix the problem by limiting the minimum size of a partition to 4 sockets even if only 2 are configured.
Signed-off-by: Mike Travis <[email protected]> Acked-by: Dimitri Sivanich <[email protected]> Reviewed-by: Russ Anderson <[email protected]> --- arch/x86/kernel/apic/x2apic_uv_x.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c +++ linux/arch/x86/kernel/apic/x2apic_uv_x.c @@ -56,6 +56,7 @@ static struct { unsigned int socketid_shift; /* aka pnode_shift for UV1/2/3 */ unsigned int pnode_mask; unsigned int gpa_shift; + unsigned int gnode_shift; } uv_cpuid; int uv_min_hub_revision_id; @@ -133,6 +134,7 @@ static int __init early_get_pnodeid(void break; case UV4_HUB_PART_NUMBER: uv_min_hub_revision_id += UV4_HUB_REVISION_BASE - 1; + uv_cpuid.gnode_shift = 2; /* min partition is 4 sockets */ break; } @@ -1074,8 +1076,10 @@ void __init uv_init_hub_info(struct uv_h (1UL << uv_cpuid.gpa_shift) - 1; node_id.v = uv_read_local_mmr(UVH_NODE_ID); + uv_cpuid.gnode_shift = max_t(unsigned int, + uv_cpuid.gnode_shift, mn.n_val); hub_info->gnode_extra = - (node_id.s.node_id & ~((1 << mn.n_val) - 1)) >> 1; + (node_id.s.node_id & ~((1 << uv_cpuid.gnode_shift) - 1)) >> 1; hub_info->gnode_upper = ((unsigned long)hub_info->gnode_extra << mn.m_val); --
