Commit-ID: 3eae49ca8954f958b2001ab5643ef302cb7b67c7 Gitweb: http://git.kernel.org/tip/3eae49ca8954f958b2001ab5643ef302cb7b67c7 Author: cpw <[email protected]> AuthorDate: Tue, 3 Dec 2013 17:15:30 -0600 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 10 Dec 2013 10:06:00 +0100
x86/UV: Fix NULL pointer dereference in uv_flush_tlb_others() if the 'nobau' boot option is used The SGI UV tlb shootdown code panics the system with a NULL pointer deference if 'nobau' is specified on the boot commandline. uv_flush_tlb_other() gets called for every flush, whether the BAU is disabled or not. It should not be keeping the s_enters statistic while the BAU is disabled. The panic occurs because during initialization init_per_cpu_tunables() does not set the bcp->statp pointer if 'nobau' was specified. Signed-off-by: Cliff Wickman <[email protected]> Cc: <[email protected]> # 3.12.x Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/platform/uv/tlb_uv.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c index 0f92173..efe4d72 100644 --- a/arch/x86/platform/uv/tlb_uv.c +++ b/arch/x86/platform/uv/tlb_uv.c @@ -1070,12 +1070,13 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask, unsigned long status; bcp = &per_cpu(bau_control, cpu); - stat = bcp->statp; - stat->s_enters++; if (bcp->nobau) return cpumask; + stat = bcp->statp; + stat->s_enters++; + if (bcp->busy) { descriptor_status = read_lmmr(UVH_LB_BAU_SB_ACTIVATION_STATUS_0); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
