Hi, On Mon, May 06, 2019 at 04:32:35PM +0200, Greg Kroah-Hartman wrote: > [ Upstream commit 298a32b132087550d3fa80641ca58323c5dfd4d9 ] > > Commit 2d4f567103ff ("KVM: PPC: Introduce kvm_tmp framework") adds > kvm_tmp[] into the .bss section and then free the rest of unused spaces > back to the page allocator. > > kernel_init > kvm_guest_init > kvm_free_tmp > free_reserved_area > free_unref_page > free_unref_page_prepare > > With DEBUG_PAGEALLOC=y, it will unmap those pages from kernel. As the > result, kmemleak scan will trigger a panic when it scans the .bss > section with unmapped pages. > > This patch creates dedicated kmemleak objects for the .data, .bss and > potentially .data..ro_after_init sections to allow partial freeing via > the kmemleak_free_part() in the powerpc kvm_free_tmp() function. > > Link: http://lkml.kernel.org/r/20190321171917.62049-1-catalin.marinas@xxxxxxx > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> > Reported-by: Qian Cai <cai@xxxxxx> > Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc) > Tested-by: Qian Cai <cai@xxxxxx> > Cc: Paul Mackerras <paulus@xxxxxxxxx> > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Cc: Avi Kivity <avi@xxxxxxxxxx> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> > Cc: Radim Krcmar <rkrcmar@xxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > --- > arch/powerpc/kernel/kvm.c | 7 +++++++ > mm/kmemleak.c | 16 +++++++++++----- > 2 files changed, 18 insertions(+), 5 deletions(-) This commit has other problems, so we also need the following commits: commit dce5b0bdeec61bdbee56121ceb1d014151d5cab1 Author: Arnd Bergmann <arnd@xxxxxxxx> Date: Thu Apr 18 17:50:48 2019 -0700 mm/kmemleak.c: fix unused-function warning The only references outside of the #ifdef have been removed, so now we get a warning in non-SMP configurations: mm/kmemleak.c:1404:13: error: unused function 'scan_large_block' [-Werror,-Wunused-function] Add a new #ifdef around it. Link: http://lkml.kernel.org/r/20190416123148.3502045-1-arnd@xxxxxxxx Fixes: 298a32b13208 ("kmemleak: powerpc: skip scanning holes in the .bss section") Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Please apply this commit. Best regards, Nobuhiro