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 <[email protected]>
---
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 at 09:38, Jisheng Zhang <[email protected]> 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 <[email protected]>
> ---
> 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 <[email protected]> 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 <[email protected]>
> > ---
> > 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 <[email protected]>
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 <[email protected]>
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, 24 May 2021 at 12:37, Mark Rutland <[email protected]> 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 <[email protected]>
>
> 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 <[email protected]>
We also need "Cc: [email protected]", right?
Acked-by: Marco Elver <[email protected]>
Thank you both!
-- Marco
On Mon, May 24, 2021 at 12:43:56PM +0200, Marco Elver wrote:
> On Mon, 24 May 2021 at 12:37, Mark Rutland <[email protected]> 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 <[email protected]>
> >
> > 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 <[email protected]>
>
> We also need "Cc: [email protected]", 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 <[email protected]>
>
> Thank you both!
>
> -- Marco