On Tue, May 07, 2019 at 04:58:09PM +0900, Nobuhiro Iwamatsu wrote:
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@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Reported-by: Qian Cai cai@lca.pw Acked-by: Michael Ellerman mpe@ellerman.id.au (powerpc) Tested-by: Qian Cai cai@lca.pw Cc: Paul Mackerras paulus@samba.org Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Avi Kivity avi@redhat.com Cc: Paolo Bonzini pbonzini@redhat.com Cc: Radim Krcmar rkrcmar@redhat.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org
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@arndb.de 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@arndb.de Fixes: 298a32b13208 ("kmemleak: powerpc: skip scanning holes in the .bss section") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>Please apply this commit.
Now queued up, thanks!
greg k-h