[PATCH] i386 boottime for_each_cpu broken
for_each_cpu walks through all processors in cpu_possible_map, which is defined as cpu_callout_map on i386 and isn't initialised until all processors have been booted. This breaks things which do for_each_cpu iterations early during boot. So, define cpu_possible_map as a bitmap with NR_CPUS bits populated. This was triggered by a patch i'm working on which does alloc_percpu before bringing up secondary processors. From: Alexander Nyberg <alexn@telia.com> i386-boottime-for_each_cpu-broken.patch i386-boottime-for_each_cpu-broken-fix.patch The SMP version of __alloc_percpu checks the cpu_possible_map before allocating memory for a certain cpu. With the above patches the BSP cpuid is never set in cpu_possible_map which breaks CONFIG_SMP on uniprocessor machines (as soon as someone tries to dereference something allocated via __alloc_percpu, which in fact is never allocated since the cpu is not set in cpu_possible_map). Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk> Signed-off-by: Alexander Nyberg <alexn@telia.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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