Nathan Chancellor <[email protected]> writes: > After commit 0af298e62e5c ("treewide: refresh kmalloc_obj() > conversions"), there is a warning on boot for several PowerPC > configurations in QEMU: > > WARNING: mm/slub.c:5459 at ___kmalloc_large_node+0x174/0x1b0, CPU#0: > swapper/0/1 > Modules linked in: > CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted > 7.4.0-rc1-00262-g0af298e62e5c #1 PREEMPT(lazy) > NIP [c0000000006074e4] ___kmalloc_large_node+0x174/0x1b0 > LR [c00000000060782c] __kmalloc_large_node_noprof+0x3c/0x150 > Call Trace: > ... > [c00000000369fb60] [c000000000614ff0] __kmalloc_noprof+0x490/0x690 > [c00000000369fbe0] [c000000000051308] _kzalloc_noprof.constprop.0+0x1c/0x74 > [c00000000369fc00] [c00000000200b450] init_thread_group_cache_map+0xc0/0x2c4 > ... > > In this case, of_property_count_u32_elems() returns -EINVAL because > there is no "ibm,thread-groups" property. When kcalloc() was used to > allocate thread_group_array, the multiplication overflow check in > _kmalloc_array_noprof() caught that a really large allocation was > requested (as -EINVAL was converted to size_t) and returned NULL. > kzalloc_objs() has no such check, so the large allocation check in > __kmalloc_large_noprof() triggers the visible warning above. > > Check if of_property_count_u32_elems() has returned an error and bail > out if so, clearing up the warning. > > Fixes: 790a1662d3a2 ("powerpc/smp: Parse ibm,thread-groups with multiple > properties") > Signed-off-by: Nathan Chancellor <[email protected]> > --- > arch/powerpc/kernel/smp.c | 2 ++ > 1 file changed, 2 insertions(+)
Thanks for fixing it. Looks good to me. Please feel free to add: Reviewed-by: Ritesh Harjani (IBM) <[email protected]>
