From: Jeff Dike There is absolutely no reason to flush the kernel's VM area during a tlb_flush_mm. This results in a noticable performance increase in the kernel build benchmark. Signed-off-by: Jeff Dike Cc: Paolo Giarrusso Paolo said: Andrew: hold off this one, definitely. Jeff: Have you verified this with both modules enabled and iptables (a vmalloc user) compiled modularly? Maybe even non-modular iptables will trigger the bug but let's go for sure. This situation killed a conceptually similar patch in 2.4.24-2um (which did apply until 2.6.11): Signed-off-by: Andrew Morton --- arch/um/kernel/skas/tlb.c | 1 - 1 files changed, 1 deletion(-) diff -puN arch/um/kernel/skas/tlb.c~uml-kill-some-useless-vmalloc-tlb-flushing arch/um/kernel/skas/tlb.c --- devel/arch/um/kernel/skas/tlb.c~uml-kill-some-useless-vmalloc-tlb-flushing 2005-07-05 18:53:53.000000000 -0700 +++ devel-akpm/arch/um/kernel/skas/tlb.c 2005-07-05 18:53:53.000000000 -0700 @@ -76,7 +76,6 @@ void flush_tlb_mm_skas(struct mm_struct return; fix_range(mm, 0, host_task_size, 0); - flush_tlb_kernel_range_common(start_vm, end_vm); } void force_flush_all_skas(void) _