diff mbox series

[v3] riscv: set max_pfn to the PFN of the last page

Message ID 1587970764-4393-1-git-send-email-vincent.chen@sifive.com (mailing list archive)
State New, archived
Headers show
Series [v3] riscv: set max_pfn to the PFN of the last page | expand

Commit Message

Vincent Chen April 27, 2020, 6:59 a.m. UTC
The current max_pfn equals to zero. In this case, I found it caused users
cannot get some page information through /proc such as kpagecount in v5.6
kernel because of new sanity checks. The following message is displayed by
stress-ng test suite with the command "stress-ng --verbose --physpage 1 -t
1" on HiFive unleashed board.

 # stress-ng --verbose --physpage 1 -t 1
 stress-ng: debug: [109] 4 processors online, 4 processors configured
 stress-ng: info: [109] dispatching hogs: 1 physpage
 stress-ng: debug: [109] cache allocate: reducing cache level from L3 (too high) to L0
 stress-ng: debug: [109] get_cpu_cache: invalid cache_level: 0
 stress-ng: info: [109] cache allocate: using built-in defaults as no suitable cache found
 stress-ng: debug: [109] cache allocate: default cache size: 2048K
 stress-ng: debug: [109] starting stressors
 stress-ng: debug: [109] 1 stressor spawned
 stress-ng: debug: [110] stress-ng-physpage: started [110] (instance 0)
 stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd34de000 in /proc/kpagecount, errno=0 (Success)
 stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
 ...
 stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
 stress-ng: debug: [110] stress-ng-physpage: exited [110] (instance 0)
 stress-ng: debug: [109] process [110] terminated
 stress-ng: info: [109] successful run completed in 1.00s
 #

After applying this patch, the kernel can pass the test.

 # stress-ng --verbose --physpage 1 -t 1
 stress-ng: debug: [104] 4 processors online, 4 processors configured stress-ng: info: [104] dispatching hogs: 1 physpage
 stress-ng: info: [104] cache allocate: using defaults, can't determine cache details from sysfs
 stress-ng: debug: [104] cache allocate: default cache size: 2048K
 stress-ng: debug: [104] starting stressors
 stress-ng: debug: [104] 1 stressor spawned
 stress-ng: debug: [105] stress-ng-physpage: started [105] (instance 0) stress-ng: debug: [105] stress-ng-physpage: exited [105] (instance 0) stress-ng: debug: [104] process [105] terminated
 stress-ng: info: [104] successful run completed in 1.01s
 #

Fixes: 0651c263c8e3 (RISC-V: Move setup_bootmem() to mm/init.c)
Cc: stable@vger.kernel.org

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Yash Shah <yash.shah@sifive.com>
Tested-by: Yash Shah <yash.shah@sifive.com>

Changes since v1:
1. Add Fixes line and Cc stable kernel
Changes since v2:
1. Fix typo in Anup email address
---
 arch/riscv/mm/init.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Palmer Dabbelt May 4, 2020, 9:13 p.m. UTC | #1
On Sun, 26 Apr 2020 23:59:24 PDT (-0700), vincent.chen@sifive.com wrote:
> The current max_pfn equals to zero. In this case, I found it caused users
> cannot get some page information through /proc such as kpagecount in v5.6
> kernel because of new sanity checks. The following message is displayed by
> stress-ng test suite with the command "stress-ng --verbose --physpage 1 -t
> 1" on HiFive unleashed board.
>
>  # stress-ng --verbose --physpage 1 -t 1
>  stress-ng: debug: [109] 4 processors online, 4 processors configured
>  stress-ng: info: [109] dispatching hogs: 1 physpage
>  stress-ng: debug: [109] cache allocate: reducing cache level from L3 (too high) to L0
>  stress-ng: debug: [109] get_cpu_cache: invalid cache_level: 0
>  stress-ng: info: [109] cache allocate: using built-in defaults as no suitable cache found
>  stress-ng: debug: [109] cache allocate: default cache size: 2048K
>  stress-ng: debug: [109] starting stressors
>  stress-ng: debug: [109] 1 stressor spawned
>  stress-ng: debug: [110] stress-ng-physpage: started [110] (instance 0)
>  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd34de000 in /proc/kpagecount, errno=0 (Success)
>  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
>  ...
>  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
>  stress-ng: debug: [110] stress-ng-physpage: exited [110] (instance 0)
>  stress-ng: debug: [109] process [110] terminated
>  stress-ng: info: [109] successful run completed in 1.00s
>  #
>
> After applying this patch, the kernel can pass the test.
>
>  # stress-ng --verbose --physpage 1 -t 1
>  stress-ng: debug: [104] 4 processors online, 4 processors configured stress-ng: info: [104] dispatching hogs: 1 physpage
>  stress-ng: info: [104] cache allocate: using defaults, can't determine cache details from sysfs
>  stress-ng: debug: [104] cache allocate: default cache size: 2048K
>  stress-ng: debug: [104] starting stressors
>  stress-ng: debug: [104] 1 stressor spawned
>  stress-ng: debug: [105] stress-ng-physpage: started [105] (instance 0) stress-ng: debug: [105] stress-ng-physpage: exited [105] (instance 0) stress-ng: debug: [104] process [105] terminated
>  stress-ng: info: [104] successful run completed in 1.01s
>  #
>
> Fixes: 0651c263c8e3 (RISC-V: Move setup_bootmem() to mm/init.c)
> Cc: stable@vger.kernel.org
>
> Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
> Reviewed-by: Anup Patel <anup@brainfault.org>
> Reviewed-by: Yash Shah <yash.shah@sifive.com>
> Tested-by: Yash Shah <yash.shah@sifive.com>
>
> Changes since v1:
> 1. Add Fixes line and Cc stable kernel
> Changes since v2:
> 1. Fix typo in Anup email address
> ---
>  arch/riscv/mm/init.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index fab855963c73..157924baa191 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -149,7 +149,8 @@ void __init setup_bootmem(void)
>  	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
>
>  	set_max_mapnr(PFN_DOWN(mem_size));
> -	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
> +	max_pfn = PFN_DOWN(memblock_end_of_DRAM());
> +	max_low_pfn = max_pfn;
>
>  #ifdef CONFIG_BLK_DEV_INITRD
>  	setup_initrd();

I'm dropping the Fixes tag, as the actual bug goes back farther than that
commit, that's just as far as it'll auto-apply.
Guo Ren Jan. 28, 2021, 1:54 a.m. UTC | #2
Hi Palmer & Vicent,

Please have a look at the patch:

https://lore.kernel.org/linux-riscv/20210121063117.3164494-1-guoren@kernel.org/T/#u

Seems our set_max_mapnr is wrong and it will make pfn_valid fault in
non-zero start-address.

On Tue, May 5, 2020 at 5:14 AM Palmer Dabbelt <palmer@dabbelt.com> wrote:
>
> On Sun, 26 Apr 2020 23:59:24 PDT (-0700), vincent.chen@sifive.com wrote:
> > The current max_pfn equals to zero. In this case, I found it caused users
> > cannot get some page information through /proc such as kpagecount in v5.6
> > kernel because of new sanity checks. The following message is displayed by
> > stress-ng test suite with the command "stress-ng --verbose --physpage 1 -t
> > 1" on HiFive unleashed board.
> >
> >  # stress-ng --verbose --physpage 1 -t 1
> >  stress-ng: debug: [109] 4 processors online, 4 processors configured
> >  stress-ng: info: [109] dispatching hogs: 1 physpage
> >  stress-ng: debug: [109] cache allocate: reducing cache level from L3 (too high) to L0
> >  stress-ng: debug: [109] get_cpu_cache: invalid cache_level: 0
> >  stress-ng: info: [109] cache allocate: using built-in defaults as no suitable cache found
> >  stress-ng: debug: [109] cache allocate: default cache size: 2048K
> >  stress-ng: debug: [109] starting stressors
> >  stress-ng: debug: [109] 1 stressor spawned
> >  stress-ng: debug: [110] stress-ng-physpage: started [110] (instance 0)
> >  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd34de000 in /proc/kpagecount, errno=0 (Success)
> >  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
> >  ...
> >  stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success)
> >  stress-ng: debug: [110] stress-ng-physpage: exited [110] (instance 0)
> >  stress-ng: debug: [109] process [110] terminated
> >  stress-ng: info: [109] successful run completed in 1.00s
> >  #
> >
> > After applying this patch, the kernel can pass the test.
> >
> >  # stress-ng --verbose --physpage 1 -t 1
> >  stress-ng: debug: [104] 4 processors online, 4 processors configured stress-ng: info: [104] dispatching hogs: 1 physpage
> >  stress-ng: info: [104] cache allocate: using defaults, can't determine cache details from sysfs
> >  stress-ng: debug: [104] cache allocate: default cache size: 2048K
> >  stress-ng: debug: [104] starting stressors
> >  stress-ng: debug: [104] 1 stressor spawned
> >  stress-ng: debug: [105] stress-ng-physpage: started [105] (instance 0) stress-ng: debug: [105] stress-ng-physpage: exited [105] (instance 0) stress-ng: debug: [104] process [105] terminated
> >  stress-ng: info: [104] successful run completed in 1.01s
> >  #
> >
> > Fixes: 0651c263c8e3 (RISC-V: Move setup_bootmem() to mm/init.c)
> > Cc: stable@vger.kernel.org
> >
> > Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
> > Reviewed-by: Anup Patel <anup@brainfault.org>
> > Reviewed-by: Yash Shah <yash.shah@sifive.com>
> > Tested-by: Yash Shah <yash.shah@sifive.com>
> >
> > Changes since v1:
> > 1. Add Fixes line and Cc stable kernel
> > Changes since v2:
> > 1. Fix typo in Anup email address
> > ---
> >  arch/riscv/mm/init.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> > index fab855963c73..157924baa191 100644
> > --- a/arch/riscv/mm/init.c
> > +++ b/arch/riscv/mm/init.c
> > @@ -149,7 +149,8 @@ void __init setup_bootmem(void)
> >       memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
> >
> >       set_max_mapnr(PFN_DOWN(mem_size));
> > -     max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
> > +     max_pfn = PFN_DOWN(memblock_end_of_DRAM());
> > +     max_low_pfn = max_pfn;
> >
> >  #ifdef CONFIG_BLK_DEV_INITRD
> >       setup_initrd();
>
> I'm dropping the Fixes tag, as the actual bug goes back farther than that
> commit, that's just as far as it'll auto-apply.
>
diff mbox series

Patch

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index fab855963c73..157924baa191 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -149,7 +149,8 @@  void __init setup_bootmem(void)
 	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
 
 	set_max_mapnr(PFN_DOWN(mem_size));
-	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	max_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	max_low_pfn = max_pfn;
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	setup_initrd();