Message ID | 20210524153659.58a707a9@xhacker.debian (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | arm64: mm: don't use CON and BLK mapping if KFENCE is enabled | expand |
On Mon, 24 May 2021 at 09:38, Jisheng Zhang <Jisheng.Zhang@synaptics.com> wrote: > > Fix below warning if KFENCE=y but RODATA_FULL=n: > Is this patch still relevant given you just sent "arm64: remove page granularity limitation from KFENCE" ? > [ 0.000000] ------------[ cut here ]------------ > [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/memory.c:2462 apply_to_pmd_range+0xec/0x190 > [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc1+ #10 > [ 0.000000] Hardware name: linux,dummy-virt (DT) > [ 0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO BTYPE=--) > [ 0.000000] pc : apply_to_pmd_range+0xec/0x190 > [ 0.000000] lr : __apply_to_page_range+0x94/0x170 > [ 0.000000] sp : ffffffc010573e20 > [ 0.000000] x29: ffffffc010573e20 x28: ffffff801f400000 x27: ffffff801f401000 > [ 0.000000] x26: 0000000000000001 x25: ffffff801f400fff x24: ffffffc010573f28 > [ 0.000000] x23: ffffffc01002b710 x22: ffffffc0105fa450 x21: ffffffc010573ee4 > [ 0.000000] x20: ffffff801fffb7d0 x19: ffffff801f401000 x18: 00000000fffffffe > [ 0.000000] x17: 000000000000003f x16: 000000000000000a x15: ffffffc01060b940 > [ 0.000000] x14: 0000000000000000 x13: 0098968000000000 x12: 0000000098968000 > [ 0.000000] x11: 0000000000000000 x10: 0000000098968000 x9 : 0000000000000001 > [ 0.000000] x8 : 0000000000000000 x7 : ffffffc010573ee4 x6 : 0000000000000001 > [ 0.000000] x5 : ffffffc010573f28 x4 : ffffffc01002b710 x3 : 0000000040000000 > [ 0.000000] x2 : ffffff801f5fffff x1 : 0000000000000001 x0 : 007800005f400705 > [ 0.000000] Call trace: > [ 0.000000] apply_to_pmd_range+0xec/0x190 > [ 0.000000] __apply_to_page_range+0x94/0x170 > [ 0.000000] apply_to_page_range+0x10/0x20 > [ 0.000000] __change_memory_common+0x50/0xdc > [ 0.000000] set_memory_valid+0x30/0x40 > [ 0.000000] kfence_init_pool+0x9c/0x16c > [ 0.000000] kfence_init+0x20/0x98 > [ 0.000000] start_kernel+0x284/0x3f8 > > Fixes: 840b23986344 ("arm64, kfence: enable KFENCE for ARM64") > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > --- > arch/arm64/mm/mmu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index 6dd9369e3ea0..89b66ef43a0f 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -515,7 +515,8 @@ static void __init map_mem(pgd_t *pgdp) > */ > BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end)); > > - if (rodata_full || crash_mem_map || debug_pagealloc_enabled()) > + if (rodata_full || crash_mem_map || debug_pagealloc_enabled() || > + IS_ENABLED(CONFIG_KFENCE)) > flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; > > /* > -- > 2.31.0 >
On Mon, 24 May 2021 12:05:21 +0200 Marco Elver wrote: > > > On Mon, 24 May 2021 at 09:38, Jisheng Zhang <Jisheng.Zhang@synaptics.com> wrote: > > > > Fix below warning if KFENCE=y but RODATA_FULL=n: > > > > Is this patch still relevant given you just sent "arm64: remove page > granularity limitation from KFENCE" ? This patch fixes a bug, so I suppose it needs to merged for linux-5.13-rcN While the "arm64: remove page granularity limitation from KFENCE" series is an optimization, so it need to wait for next version, I.E linux-5.14 thanks > > > [ 0.000000] ------------[ cut here ]------------ > > [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/memory.c:2462 apply_to_pmd_range+0xec/0x190 > > [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc1+ #10 > > [ 0.000000] Hardware name: linux,dummy-virt (DT) > > [ 0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO BTYPE=--) > > [ 0.000000] pc : apply_to_pmd_range+0xec/0x190 > > [ 0.000000] lr : __apply_to_page_range+0x94/0x170 > > [ 0.000000] sp : ffffffc010573e20 > > [ 0.000000] x29: ffffffc010573e20 x28: ffffff801f400000 x27: ffffff801f401000 > > [ 0.000000] x26: 0000000000000001 x25: ffffff801f400fff x24: ffffffc010573f28 > > [ 0.000000] x23: ffffffc01002b710 x22: ffffffc0105fa450 x21: ffffffc010573ee4 > > [ 0.000000] x20: ffffff801fffb7d0 x19: ffffff801f401000 x18: 00000000fffffffe > > [ 0.000000] x17: 000000000000003f x16: 000000000000000a x15: ffffffc01060b940 > > [ 0.000000] x14: 0000000000000000 x13: 0098968000000000 x12: 0000000098968000 > > [ 0.000000] x11: 0000000000000000 x10: 0000000098968000 x9 : 0000000000000001 > > [ 0.000000] x8 : 0000000000000000 x7 : ffffffc010573ee4 x6 : 0000000000000001 > > [ 0.000000] x5 : ffffffc010573f28 x4 : ffffffc01002b710 x3 : 0000000040000000 > > [ 0.000000] x2 : ffffff801f5fffff x1 : 0000000000000001 x0 : 007800005f400705 > > [ 0.000000] Call trace: > > [ 0.000000] apply_to_pmd_range+0xec/0x190 > > [ 0.000000] __apply_to_page_range+0x94/0x170 > > [ 0.000000] apply_to_page_range+0x10/0x20 > > [ 0.000000] __change_memory_common+0x50/0xdc > > [ 0.000000] set_memory_valid+0x30/0x40 > > [ 0.000000] kfence_init_pool+0x9c/0x16c > > [ 0.000000] kfence_init+0x20/0x98 > > [ 0.000000] start_kernel+0x284/0x3f8 > > > > Fixes: 840b23986344 ("arm64, kfence: enable KFENCE for ARM64") > > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > > --- > > arch/arm64/mm/mmu.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > > index 6dd9369e3ea0..89b66ef43a0f 100644 > > --- a/arch/arm64/mm/mmu.c > > +++ b/arch/arm64/mm/mmu.c > > @@ -515,7 +515,8 @@ static void __init map_mem(pgd_t *pgdp) > > */ > > BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end)); > > > > - if (rodata_full || crash_mem_map || debug_pagealloc_enabled()) > > + if (rodata_full || crash_mem_map || debug_pagealloc_enabled() || > > + IS_ENABLED(CONFIG_KFENCE)) > > flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; > > > > /* > > -- > > 2.31.0 > >
On Mon, May 24, 2021 at 03:36:59PM +0800, Jisheng Zhang wrote: > Fix below warning if KFENCE=y but RODATA_FULL=n: > > [ 0.000000] ------------[ cut here ]------------ > [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/memory.c:2462 apply_to_pmd_range+0xec/0x190 > [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc1+ #10 > [ 0.000000] Hardware name: linux,dummy-virt (DT) > [ 0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO BTYPE=--) > [ 0.000000] pc : apply_to_pmd_range+0xec/0x190 > [ 0.000000] lr : __apply_to_page_range+0x94/0x170 > [ 0.000000] sp : ffffffc010573e20 > [ 0.000000] x29: ffffffc010573e20 x28: ffffff801f400000 x27: ffffff801f401000 > [ 0.000000] x26: 0000000000000001 x25: ffffff801f400fff x24: ffffffc010573f28 > [ 0.000000] x23: ffffffc01002b710 x22: ffffffc0105fa450 x21: ffffffc010573ee4 > [ 0.000000] x20: ffffff801fffb7d0 x19: ffffff801f401000 x18: 00000000fffffffe > [ 0.000000] x17: 000000000000003f x16: 000000000000000a x15: ffffffc01060b940 > [ 0.000000] x14: 0000000000000000 x13: 0098968000000000 x12: 0000000098968000 > [ 0.000000] x11: 0000000000000000 x10: 0000000098968000 x9 : 0000000000000001 > [ 0.000000] x8 : 0000000000000000 x7 : ffffffc010573ee4 x6 : 0000000000000001 > [ 0.000000] x5 : ffffffc010573f28 x4 : ffffffc01002b710 x3 : 0000000040000000 > [ 0.000000] x2 : ffffff801f5fffff x1 : 0000000000000001 x0 : 007800005f400705 > [ 0.000000] Call trace: > [ 0.000000] apply_to_pmd_range+0xec/0x190 > [ 0.000000] __apply_to_page_range+0x94/0x170 > [ 0.000000] apply_to_page_range+0x10/0x20 > [ 0.000000] __change_memory_common+0x50/0xdc > [ 0.000000] set_memory_valid+0x30/0x40 > [ 0.000000] kfence_init_pool+0x9c/0x16c > [ 0.000000] kfence_init+0x20/0x98 > [ 0.000000] start_kernel+0x284/0x3f8 > > Fixes: 840b23986344 ("arm64, kfence: enable KFENCE for ARM64") > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> It would be good if the commit message could explain the problem more thoroughly, e.g. | When we added KFENCE support for arm64, we intended that it would | force the entire linear map to be mapped at page granularity, but we | only enforced this in arch_add_memory() and not in map_mem(), so | memory mapped at boot time can be mapped at a larger granularity. | | When booting a kernel with KFENCE=y and RODATA_FULL=n, this results in | the following WARNING at boot: | | < warning here > With that: Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > arch/arm64/mm/mmu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index 6dd9369e3ea0..89b66ef43a0f 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -515,7 +515,8 @@ static void __init map_mem(pgd_t *pgdp) > */ > BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end)); > > - if (rodata_full || crash_mem_map || debug_pagealloc_enabled()) > + if (rodata_full || crash_mem_map || debug_pagealloc_enabled() || > + IS_ENABLED(CONFIG_KFENCE)) > flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; > > /* > -- > 2.31.0 >
On Mon, May 24, 2021 at 12:43:56PM +0200, Marco Elver wrote: > On Mon, 24 May 2021 at 12:37, Mark Rutland <mark.rutland@arm.com> wrote: > > > > On Mon, May 24, 2021 at 03:36:59PM +0800, Jisheng Zhang wrote: > > > Fix below warning if KFENCE=y but RODATA_FULL=n: > > > > > > [ 0.000000] ------------[ cut here ]------------ > > > [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/memory.c:2462 apply_to_pmd_range+0xec/0x190 > > > [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc1+ #10 > > > [ 0.000000] Hardware name: linux,dummy-virt (DT) > > > [ 0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO BTYPE=--) > > > [ 0.000000] pc : apply_to_pmd_range+0xec/0x190 > > > [ 0.000000] lr : __apply_to_page_range+0x94/0x170 > > > [ 0.000000] sp : ffffffc010573e20 > > > [ 0.000000] x29: ffffffc010573e20 x28: ffffff801f400000 x27: ffffff801f401000 > > > [ 0.000000] x26: 0000000000000001 x25: ffffff801f400fff x24: ffffffc010573f28 > > > [ 0.000000] x23: ffffffc01002b710 x22: ffffffc0105fa450 x21: ffffffc010573ee4 > > > [ 0.000000] x20: ffffff801fffb7d0 x19: ffffff801f401000 x18: 00000000fffffffe > > > [ 0.000000] x17: 000000000000003f x16: 000000000000000a x15: ffffffc01060b940 > > > [ 0.000000] x14: 0000000000000000 x13: 0098968000000000 x12: 0000000098968000 > > > [ 0.000000] x11: 0000000000000000 x10: 0000000098968000 x9 : 0000000000000001 > > > [ 0.000000] x8 : 0000000000000000 x7 : ffffffc010573ee4 x6 : 0000000000000001 > > > [ 0.000000] x5 : ffffffc010573f28 x4 : ffffffc01002b710 x3 : 0000000040000000 > > > [ 0.000000] x2 : ffffff801f5fffff x1 : 0000000000000001 x0 : 007800005f400705 > > > [ 0.000000] Call trace: > > > [ 0.000000] apply_to_pmd_range+0xec/0x190 > > > [ 0.000000] __apply_to_page_range+0x94/0x170 > > > [ 0.000000] apply_to_page_range+0x10/0x20 > > > [ 0.000000] __change_memory_common+0x50/0xdc > > > [ 0.000000] set_memory_valid+0x30/0x40 > > > [ 0.000000] kfence_init_pool+0x9c/0x16c > > > [ 0.000000] kfence_init+0x20/0x98 > > > [ 0.000000] start_kernel+0x284/0x3f8 > > > > > > Fixes: 840b23986344 ("arm64, kfence: enable KFENCE for ARM64") > > > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > > > > It would be good if the commit message could explain the problem more > > thoroughly, e.g. > > > > | When we added KFENCE support for arm64, we intended that it would > > | force the entire linear map to be mapped at page granularity, but we > > | only enforced this in arch_add_memory() and not in map_mem(), so > > | memory mapped at boot time can be mapped at a larger granularity. > > | > > | When booting a kernel with KFENCE=y and RODATA_FULL=n, this results in > > | the following WARNING at boot: > > | > > | < warning here > > > > > With that: > > > > Acked-by: Mark Rutland <mark.rutland@arm.com> > > We also need "Cc: stable@vger.kernel.org", right? That would be a good idea, yes. I can't recall whether "Fixes" alone is intended to be sufficient or not to trigger a backport. Mark. > Acked-by: Marco Elver <elver@google.com> > > Thank you both! > > -- Marco
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 6dd9369e3ea0..89b66ef43a0f 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -515,7 +515,8 @@ static void __init map_mem(pgd_t *pgdp) */ BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end)); - if (rodata_full || crash_mem_map || debug_pagealloc_enabled()) + if (rodata_full || crash_mem_map || debug_pagealloc_enabled() || + IS_ENABLED(CONFIG_KFENCE)) flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; /*
Fix below warning if KFENCE=y but RODATA_FULL=n: [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/memory.c:2462 apply_to_pmd_range+0xec/0x190 [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-rc1+ #10 [ 0.000000] Hardware name: linux,dummy-virt (DT) [ 0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO BTYPE=--) [ 0.000000] pc : apply_to_pmd_range+0xec/0x190 [ 0.000000] lr : __apply_to_page_range+0x94/0x170 [ 0.000000] sp : ffffffc010573e20 [ 0.000000] x29: ffffffc010573e20 x28: ffffff801f400000 x27: ffffff801f401000 [ 0.000000] x26: 0000000000000001 x25: ffffff801f400fff x24: ffffffc010573f28 [ 0.000000] x23: ffffffc01002b710 x22: ffffffc0105fa450 x21: ffffffc010573ee4 [ 0.000000] x20: ffffff801fffb7d0 x19: ffffff801f401000 x18: 00000000fffffffe [ 0.000000] x17: 000000000000003f x16: 000000000000000a x15: ffffffc01060b940 [ 0.000000] x14: 0000000000000000 x13: 0098968000000000 x12: 0000000098968000 [ 0.000000] x11: 0000000000000000 x10: 0000000098968000 x9 : 0000000000000001 [ 0.000000] x8 : 0000000000000000 x7 : ffffffc010573ee4 x6 : 0000000000000001 [ 0.000000] x5 : ffffffc010573f28 x4 : ffffffc01002b710 x3 : 0000000040000000 [ 0.000000] x2 : ffffff801f5fffff x1 : 0000000000000001 x0 : 007800005f400705 [ 0.000000] Call trace: [ 0.000000] apply_to_pmd_range+0xec/0x190 [ 0.000000] __apply_to_page_range+0x94/0x170 [ 0.000000] apply_to_page_range+0x10/0x20 [ 0.000000] __change_memory_common+0x50/0xdc [ 0.000000] set_memory_valid+0x30/0x40 [ 0.000000] kfence_init_pool+0x9c/0x16c [ 0.000000] kfence_init+0x20/0x98 [ 0.000000] start_kernel+0x284/0x3f8 Fixes: 840b23986344 ("arm64, kfence: enable KFENCE for ARM64") Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> --- arch/arm64/mm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)