On Mon, Mar 29, 2021 at 03:08:52PM +0200, Ard Biesheuvel wrote:
> On Mon, 29 Mar 2021 at 12:12, Greg Kroah-Hartman
> <gre...@linuxfoundation.org> wrote:
> >
> > On Mon, Mar 29, 2021 at 03:05:25PM +0530, Naresh Kamboju wrote:
> > > On Mon, 29 Mar 2021 at 14:10, Greg Kroah-Hartman
> > > <gre...@linuxfoundation.org> wrote:
> > > >
> > > > From: Anshuman Khandual <anshuman.khand...@arm.com>
> > > >
> > > > [ Upstream commit 03aaf83fba6e5af08b5dd174c72edee9b7d9ed9b ]
> > > >
> > > > This overrides arch_get_mappable_range() on arm64 platform which will be
> > > > used with recently added generic framework. It drops
> > > > inside_linear_region() and subsequent check in arch_add_memory() which
> > > > are
> > > > no longer required. It also adds a VM_BUG_ON() check that would ensure
> > > > that mhp_range_allowed() has already been called.
> > > >
> > > > Link:
> > > > https://lkml.kernel.org/r/1612149902-7867-3-git-send-email-anshuman.khand...@arm.com
> > > > Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com>
> > > > Reviewed-by: David Hildenbrand <da...@redhat.com>
> > > > Reviewed-by: Catalin Marinas <catalin.mari...@arm.com>
> > > > Cc: Will Deacon <w...@kernel.org>
> > > > Cc: Ard Biesheuvel <a...@kernel.org>
> > > > Cc: Mark Rutland <mark.rutl...@arm.com>
> > > > Cc: Heiko Carstens <h...@linux.ibm.com>
> > > > Cc: Jason Wang <jasow...@redhat.com>
> > > > Cc: Jonathan Cameron <jonathan.came...@huawei.com>
> > > > Cc: "Michael S. Tsirkin" <m...@redhat.com>
> > > > Cc: Michal Hocko <mho...@kernel.org>
> > > > Cc: Oscar Salvador <osalva...@suse.de>
> > > > Cc: Pankaj Gupta <pankaj.gu...@cloud.ionos.com>
> > > > Cc: Pankaj Gupta <pankaj.gupta.li...@gmail.com>
> > > > Cc: teawater <teawat...@linux.alibaba.com>
> > > > Cc: Vasily Gorbik <g...@linux.ibm.com>
> > > > Cc: Wei Yang <richard.weiy...@linux.alibaba.com>
> > > > Signed-off-by: Andrew Morton <a...@linux-foundation.org>
> > > > Signed-off-by: Linus Torvalds <torva...@linux-foundation.org>
> > > > Signed-off-by: Sasha Levin <sas...@kernel.org>
> > > > ---
> > > > arch/arm64/mm/mmu.c | 15 +++++++--------
> > > > 1 file changed, 7 insertions(+), 8 deletions(-)
> > > >
> > > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> > > > index 6f0648777d34..92b3be127796 100644
> > > > --- a/arch/arm64/mm/mmu.c
> > > > +++ b/arch/arm64/mm/mmu.c
> > > > @@ -1443,16 +1443,19 @@ static void __remove_pgd_mapping(pgd_t *pgdir,
> > > > unsigned long start, u64 size)
> > > > free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
> > > > }
> > > >
> > > > -static bool inside_linear_region(u64 start, u64 size)
> > > > +struct range arch_get_mappable_range(void)
> > > > {
> > > > + struct range mhp_range;
> > > > +
> > > > /*
> > > > * Linear mapping region is the range [PAGE_OFFSET..(PAGE_END -
> > > > 1)]
> > > > * accommodating both its ends but excluding PAGE_END. Max
> > > > physical
> > > > * range which can be mapped inside this linear mapping range,
> > > > must
> > > > * also be derived from its end points.
> > > > */
> > > > - return start >= __pa(_PAGE_OFFSET(vabits_actual)) &&
> > > > - (start + size - 1) <= __pa(PAGE_END - 1);
> > > > + mhp_range.start = __pa(_PAGE_OFFSET(vabits_actual));
> > > > + mhp_range.end = __pa(PAGE_END - 1);
> > > > + return mhp_range;
> > > > }
> > > >
> > > > int arch_add_memory(int nid, u64 start, u64 size,
> > > > @@ -1460,11 +1463,7 @@ int arch_add_memory(int nid, u64 start, u64 size,
> > > > {
> > > > int ret, flags = 0;
> > > >
> > > > - if (!inside_linear_region(start, size)) {
> > > > - pr_err("[%llx %llx] is outside linear mapping
> > > > region\n", start, start + size);
> > > > - return -EINVAL;
> > > > - }
> > > > -
> > > > + VM_BUG_ON(!mhp_range_allowed(start, size, true));
> > > > if (rodata_full || debug_pagealloc_enabled())
> > > > flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
> > >
> > > The stable rc 5.10 and 5.11 builds failed for arm64 architecture
> > > due to below warnings / errors,
> > >
> > > > Anshuman Khandual <anshuman.khand...@arm.com>
> > > > arm64/mm: define arch_get_mappable_range()
> > >
> > >
> > > arch/arm64/mm/mmu.c: In function 'arch_add_memory':
> > > arch/arm64/mm/mmu.c:1483:13: error: implicit declaration of function
> > > 'mhp_range_allowed'; did you mean 'cpu_map_prog_allowed'?
> > > [-Werror=implicit-function-declaration]
> > > VM_BUG_ON(!mhp_range_allowed(start, size, true));
> > > ^
> > > include/linux/build_bug.h:30:63: note: in definition of macro
> > > 'BUILD_BUG_ON_INVALID'
> > > #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
> > > ^
> > > arch/arm64/mm/mmu.c:1483:2: note: in expansion of macro 'VM_BUG_ON'
> > > VM_BUG_ON(!mhp_range_allowed(start, size, true));
> > > ^~~~~~~~~
> > >
> > > Build link,
> > > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.11/DISTRO=lkft,MACHINE=juno,label=docker-buster-lkft/41/consoleText
> > > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.10/DISTRO=lkft,MACHINE=dragonboard-410c,label=docker-buster-lkft/120/consoleFull
> >
> > thanks, will go drop this, and the patch that was after it in the
> > series, from both trees and will push out a -rc2.
> >
>
> Why were these picked up in the first place? I don't see any fixes or
> cc:stable tags, and the commit log clearly describes that the change
> is preparatory work for enabling arm64 support into a recently
> introduced generic framework.
This was needed for a follow-on patch in the series that fixed an issue.
Specifically it was commit ee7febce0519 ("arm64: mm: correct the inside
linear map range during hotplug check")
thanks,
greg k-h
