[2/2] riscv: Fixup static_obj() fail v2

Commit Message

Guo Ren Oct. 7, 2020, 3:08 p.m. UTC

From: Guo Ren <[e-mail]>

v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
been reverted.

When enable LOCKDEP, static_obj() will cause error:

[    0.067192] INFO: trying to register non-static key.
[    0.067325] the code is fine but needs lockdep annotation.
[    0.067449] turning off the locking correctness validator.
[    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
[    0.067945] Call Trace:
[    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
[    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
[    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
[    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
[    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
[    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
[    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
[    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
[    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
[    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
[    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
[    0.069953] [<ffffffe000001092>] 0xffffffe000001092

Because some __initdata static variables is before _stext:

static int static_obj(const void *obj)
{
        unsigned long start = (unsigned long) &_stext,
                      end   = (unsigned long) &_end,
                      addr  = (unsigned long) obj;

        /*
         * static variable?
         */
        if ((addr >= start) && (addr < end))
                return 1;

	if (arch_is_kernel_data(addr))
		return 1;

We could implement arch_is_kernel_data to fixup it.

Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
Signed-off-by: Guo Ren <[e-mail]>
Reported-by: Aurelien Jarno <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: Atish Patra <[e-mail]>
Cc: Andreas Schwab <[e-mail]>
Cc: Aurelien Jarno <[e-mail]>
---
 arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
 arch/riscv/kernel/setup.c         |  9 +++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 arch/riscv/include/asm/sections.h

Comments

Atish Patra Oct. 7, 2020, 7:46 p.m. UTC | #1

On Wed, Oct 7, 2020 at 8:09 AM <[e-mail]> wrote:
>
> From: Guo Ren <[e-mail]>
>
> v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> been reverted.
>
> When enable LOCKDEP, static_obj() will cause error:
>
> [    0.067192] INFO: trying to register non-static key.
> [    0.067325] the code is fine but needs lockdep annotation.
> [    0.067449] turning off the locking correctness validator.
> [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> [    0.067945] Call Trace:
> [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
>
> Because some __initdata static variables is before _stext:
>
> static int static_obj(const void *obj)
> {
>         unsigned long start = (unsigned long) &_stext,
>                       end   = (unsigned long) &_end,
>                       addr  = (unsigned long) obj;
>
>         /*
>          * static variable?
>          */
>         if ((addr >= start) && (addr < end))
>                 return 1;
>
>         if (arch_is_kernel_data(addr))
>                 return 1;
>
> We could implement arch_is_kernel_data to fixup it.
>
> Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> Signed-off-by: Guo Ren <[e-mail]>
> Reported-by: Aurelien Jarno <[e-mail]>
> Cc: Palmer Dabbelt <[e-mail]>
> Cc: Atish Patra <[e-mail]>
> Cc: Andreas Schwab <[e-mail]>
> Cc: Aurelien Jarno <[e-mail]>
> ---
>  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
>  arch/riscv/kernel/setup.c         |  9 +++++++++
>  2 files changed, 29 insertions(+)
>  create mode 100644 arch/riscv/include/asm/sections.h
>
> diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> new file mode 100644
> index 00000000..2317b9e
> --- /dev/null
> +++ b/arch/riscv/include/asm/sections.h

You may want to rebase it on top of for-next as UEFI series also adds this file.
.

> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef _ASM_RISCV_SECTIONS_H
> +#define _ASM_RISCV_SECTIONS_H
> +
> +#define arch_is_kernel_data arch_is_kernel_data
> +
> +#include <asm-generic/sections.h>
> +
> +extern bool init_mem_is_free;
> +
> +static inline int arch_is_kernel_data(unsigned long addr)
> +{
> +       if (init_mem_is_free)
> +               return 0;
> +
> +       return addr >= (unsigned long)__init_begin &&
> +               addr < (unsigned long)__init_end;
> +}
> +#endif /* _ASM_RISCV_SECTIONS_H */
> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> index 2c6dd32..9ebd5eb4 100644
> --- a/arch/riscv/kernel/setup.c
> +++ b/arch/riscv/kernel/setup.c
> @@ -17,6 +17,7 @@
>  #include <linux/sched/task.h>
>  #include <linux/swiotlb.h>
>  #include <linux/smp.h>
> +#include <linux/poison.h>
>
>  #include <asm/cpu_ops.h>
>  #include <asm/setup.h>
> @@ -112,3 +113,11 @@ static int __init topology_init(void)
>         return 0;
>  }
>  subsys_initcall(topology_init);
> +
> +bool init_mem_is_free = false;
> +
> +void free_initmem(void)
> +{
> +       free_initmem_default(POISON_FREE_INITMEM);
> +       init_mem_is_free = true;
> +}
> --
> 2.7.4
>

Looks good. Much cleaner than the first approach.
FYI: I am still looking into separating __init text & data so that
different permissions can be applied to them.
With this patch, we can just separate it on top of _stext.


Reviewed-by: Atish Patra <[e-mail]>

Guo Ren Oct. 8, 2020, 2:30 a.m. UTC | #2

On Thu, Oct 8, 2020 at 3:46 AM Atish Patra <[e-mail]> wrote:
>
> On Wed, Oct 7, 2020 at 8:09 AM <[e-mail]> wrote:
> >
> > From: Guo Ren <[e-mail]>
> >
> > v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> > been reverted.
> >
> > When enable LOCKDEP, static_obj() will cause error:
> >
> > [    0.067192] INFO: trying to register non-static key.
> > [    0.067325] the code is fine but needs lockdep annotation.
> > [    0.067449] turning off the locking correctness validator.
> > [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> > [    0.067945] Call Trace:
> > [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> > [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> > [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> > [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> > [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> > [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> > [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> > [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> > [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> > [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> > [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> > [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
> >
> > Because some __initdata static variables is before _stext:
> >
> > static int static_obj(const void *obj)
> > {
> >         unsigned long start = (unsigned long) &_stext,
> >                       end   = (unsigned long) &_end,
> >                       addr  = (unsigned long) obj;
> >
> >         /*
> >          * static variable?
> >          */
> >         if ((addr >= start) && (addr < end))
> >                 return 1;
> >
> >         if (arch_is_kernel_data(addr))
> >                 return 1;
> >
> > We could implement arch_is_kernel_data to fixup it.
> >
> > Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> > Signed-off-by: Guo Ren <[e-mail]>
> > Reported-by: Aurelien Jarno <[e-mail]>
> > Cc: Palmer Dabbelt <[e-mail]>
> > Cc: Atish Patra <[e-mail]>
> > Cc: Andreas Schwab <[e-mail]>
> > Cc: Aurelien Jarno <[e-mail]>
> > ---
> >  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
> >  arch/riscv/kernel/setup.c         |  9 +++++++++
> >  2 files changed, 29 insertions(+)
> >  create mode 100644 arch/riscv/include/asm/sections.h
> >
> > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> > new file mode 100644
> > index 00000000..2317b9e
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/sections.h
>
> You may want to rebase it on top of for-next as UEFI series also adds this file.
ok

> .
>
> > @@ -0,0 +1,20 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +#ifndef _ASM_RISCV_SECTIONS_H
> > +#define _ASM_RISCV_SECTIONS_H
> > +
> > +#define arch_is_kernel_data arch_is_kernel_data
> > +
> > +#include <asm-generic/sections.h>
> > +
> > +extern bool init_mem_is_free;
> > +
> > +static inline int arch_is_kernel_data(unsigned long addr)
> > +{
> > +       if (init_mem_is_free)
> > +               return 0;
> > +
> > +       return addr >= (unsigned long)__init_begin &&
> > +               addr < (unsigned long)__init_end;
> > +}
> > +#endif /* _ASM_RISCV_SECTIONS_H */
> > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > index 2c6dd32..9ebd5eb4 100644
> > --- a/arch/riscv/kernel/setup.c
> > +++ b/arch/riscv/kernel/setup.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/sched/task.h>
> >  #include <linux/swiotlb.h>
> >  #include <linux/smp.h>
> > +#include <linux/poison.h>
> >
> >  #include <asm/cpu_ops.h>
> >  #include <asm/setup.h>
> > @@ -112,3 +113,11 @@ static int __init topology_init(void)
> >         return 0;
> >  }
> >  subsys_initcall(topology_init);
> > +
> > +bool init_mem_is_free = false;
> > +
> > +void free_initmem(void)
> > +{
> > +       free_initmem_default(POISON_FREE_INITMEM);
> > +       init_mem_is_free = true;
> > +}
> > --
> > 2.7.4
> >
>
> Looks good. Much cleaner than the first approach.
> FYI: I am still looking into separating __init text & data so that
> different permissions can be applied to them.
> With this patch, we can just separate it on top of _stext.
>
>
> Reviewed-by: Atish Patra <[e-mail]>
>
> --
> Regards,
> Atish

Palmer Dabbelt Oct. 8, 2020, 3:54 a.m. UTC | #3

On Wed, 07 Oct 2020 08:08:33 PDT (-0700), [e-mail] wrote:
> From: Guo Ren <[e-mail]>
>
> v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> been reverted.
>
> When enable LOCKDEP, static_obj() will cause error:
>
> [    0.067192] INFO: trying to register non-static key.
> [    0.067325] the code is fine but needs lockdep annotation.
> [    0.067449] turning off the locking correctness validator.
> [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> [    0.067945] Call Trace:
> [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
>
> Because some __initdata static variables is before _stext:
>
> static int static_obj(const void *obj)
> {
>         unsigned long start = (unsigned long) &_stext,
>                       end   = (unsigned long) &_end,
>                       addr  = (unsigned long) obj;
>
>         /*
>          * static variable?
>          */
>         if ((addr >= start) && (addr < end))
>                 return 1;
>
> 	if (arch_is_kernel_data(addr))
> 		return 1;
>
> We could implement arch_is_kernel_data to fixup it.
>
> Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> Signed-off-by: Guo Ren <[e-mail]>
> Reported-by: Aurelien Jarno <[e-mail]>
> Cc: Palmer Dabbelt <[e-mail]>
> Cc: Atish Patra <[e-mail]>
> Cc: Andreas Schwab <[e-mail]>
> Cc: Aurelien Jarno <[e-mail]>
> ---
>  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
>  arch/riscv/kernel/setup.c         |  9 +++++++++
>  2 files changed, 29 insertions(+)
>  create mode 100644 arch/riscv/include/asm/sections.h
>
> diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> new file mode 100644
> index 00000000..2317b9e
> --- /dev/null
> +++ b/arch/riscv/include/asm/sections.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef _ASM_RISCV_SECTIONS_H
> +#define _ASM_RISCV_SECTIONS_H
> +
> +#define arch_is_kernel_data arch_is_kernel_data
> +
> +#include <asm-generic/sections.h>
> +
> +extern bool init_mem_is_free;
> +
> +static inline int arch_is_kernel_data(unsigned long addr)
> +{
> +	if (init_mem_is_free)
> +		return 0;
> +
> +	return addr >= (unsigned long)__init_begin &&
> +		addr < (unsigned long)__init_end;
> +}
> +#endif /* _ASM_RISCV_SECTIONS_H */
> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> index 2c6dd32..9ebd5eb4 100644
> --- a/arch/riscv/kernel/setup.c
> +++ b/arch/riscv/kernel/setup.c
> @@ -17,6 +17,7 @@
>  #include <linux/sched/task.h>
>  #include <linux/swiotlb.h>
>  #include <linux/smp.h>
> +#include <linux/poison.h>
>
>  #include <asm/cpu_ops.h>
>  #include <asm/setup.h>
> @@ -112,3 +113,11 @@ static int __init topology_init(void)
>  	return 0;
>  }
>  subsys_initcall(topology_init);
> +
> +bool init_mem_is_free = false;
> +
> +void free_initmem(void)
> +{
> +	free_initmem_default(POISON_FREE_INITMEM);
> +	init_mem_is_free = true;
> +}

I'm a bit confused as to what you're trying to do here.  Yesterday I got
another version of this patch set that moves init data around, today a
different one.  Yesterday's is tested and simpler, and given it's so late in
the process I'm inclined to take that as I don't want to break anything.

Right now I have

84814460eef9 ("riscv: Fixup bootup failure with HARDENED_USERCOPY")
a78c6f5956a9 ("RISC-V: Make sure memblock reserves the memory containing DT")
549738f15da0 ("Linux 5.9-rc8")

Unless there's some functional bug, that's what I'm going to send out for 5.9
-- I'm not all that worried about lacking the ability to free init data.  The
above seems like fine 5.10 material.

Let me know if I'm missing something here.

Atish Patra Oct. 8, 2020, 5:57 p.m. UTC | #4

On Wed, Oct 7, 2020 at 8:54 PM Palmer Dabbelt <[e-mail]> wrote:
>
> On Wed, 07 Oct 2020 08:08:33 PDT (-0700), [e-mail] wrote:
> > From: Guo Ren <[e-mail]>
> >
> > v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> > been reverted.
> >
> > When enable LOCKDEP, static_obj() will cause error:
> >
> > [    0.067192] INFO: trying to register non-static key.
> > [    0.067325] the code is fine but needs lockdep annotation.
> > [    0.067449] turning off the locking correctness validator.
> > [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> > [    0.067945] Call Trace:
> > [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> > [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> > [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> > [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> > [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> > [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> > [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> > [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> > [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> > [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> > [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> > [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
> >
> > Because some __initdata static variables is before _stext:
> >
> > static int static_obj(const void *obj)
> > {
> >         unsigned long start = (unsigned long) &_stext,
> >                       end   = (unsigned long) &_end,
> >                       addr  = (unsigned long) obj;
> >
> >         /*
> >          * static variable?
> >          */
> >         if ((addr >= start) && (addr < end))
> >                 return 1;
> >
> >       if (arch_is_kernel_data(addr))
> >               return 1;
> >
> > We could implement arch_is_kernel_data to fixup it.
> >
> > Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> > Signed-off-by: Guo Ren <[e-mail]>
> > Reported-by: Aurelien Jarno <[e-mail]>
> > Cc: Palmer Dabbelt <[e-mail]>
> > Cc: Atish Patra <[e-mail]>
> > Cc: Andreas Schwab <[e-mail]>
> > Cc: Aurelien Jarno <[e-mail]>
> > ---
> >  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
> >  arch/riscv/kernel/setup.c         |  9 +++++++++
> >  2 files changed, 29 insertions(+)
> >  create mode 100644 arch/riscv/include/asm/sections.h
> >
> > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> > new file mode 100644
> > index 00000000..2317b9e
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/sections.h
> > @@ -0,0 +1,20 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +#ifndef _ASM_RISCV_SECTIONS_H
> > +#define _ASM_RISCV_SECTIONS_H
> > +
> > +#define arch_is_kernel_data arch_is_kernel_data
> > +
> > +#include <asm-generic/sections.h>
> > +
> > +extern bool init_mem_is_free;
> > +
> > +static inline int arch_is_kernel_data(unsigned long addr)
> > +{
> > +     if (init_mem_is_free)
> > +             return 0;
> > +
> > +     return addr >= (unsigned long)__init_begin &&
> > +             addr < (unsigned long)__init_end;
> > +}
> > +#endif /* _ASM_RISCV_SECTIONS_H */
> > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > index 2c6dd32..9ebd5eb4 100644
> > --- a/arch/riscv/kernel/setup.c
> > +++ b/arch/riscv/kernel/setup.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/sched/task.h>
> >  #include <linux/swiotlb.h>
> >  #include <linux/smp.h>
> > +#include <linux/poison.h>
> >
> >  #include <asm/cpu_ops.h>
> >  #include <asm/setup.h>
> > @@ -112,3 +113,11 @@ static int __init topology_init(void)
> >       return 0;
> >  }
> >  subsys_initcall(topology_init);
> > +
> > +bool init_mem_is_free = false;
> > +
> > +void free_initmem(void)
> > +{
> > +     free_initmem_default(POISON_FREE_INITMEM);
> > +     init_mem_is_free = true;
> > +}
>
> I'm a bit confused as to what you're trying to do here.  Yesterday I got
> another version of this patch set that moves init data around, today a
> different one.  Yesterday's is tested and simpler, and given it's so late in
> the process I'm inclined to take that as I don't want to break anything.
>

I agree. This version will have some more conflicts with other patches
and it's too late in cycle.
It's best to merge it in 5.10.

> Right now I have
>
> 84814460eef9 ("riscv: Fixup bootup failure with HARDENED_USERCOPY")
> a78c6f5956a9 ("RISC-V: Make sure memblock reserves the memory containing DT")
> 549738f15da0 ("Linux 5.9-rc8")
>
> Unless there's some functional bug, that's what I'm going to send out for 5.9
> -- I'm not all that worried about lacking the ability to free init data.  The
> above seems like fine 5.10 material.
>
> Let me know if I'm missing something here.

Guo Ren Oct. 9, 2020, 1:53 a.m. UTC | #5

On Thu, Oct 8, 2020 at 11:54 AM Palmer Dabbelt <[e-mail]> wrote:
>
> On Wed, 07 Oct 2020 08:08:33 PDT (-0700), [e-mail] wrote:
> > From: Guo Ren <[e-mail]>
> >
> > v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> > been reverted.
> >
> > When enable LOCKDEP, static_obj() will cause error:
> >
> > [    0.067192] INFO: trying to register non-static key.
> > [    0.067325] the code is fine but needs lockdep annotation.
> > [    0.067449] turning off the locking correctness validator.
> > [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> > [    0.067945] Call Trace:
> > [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> > [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> > [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> > [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> > [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> > [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> > [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> > [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> > [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> > [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> > [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> > [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
> >
> > Because some __initdata static variables is before _stext:
> >
> > static int static_obj(const void *obj)
> > {
> >         unsigned long start = (unsigned long) &_stext,
> >                       end   = (unsigned long) &_end,
> >                       addr  = (unsigned long) obj;
> >
> >         /*
> >          * static variable?
> >          */
> >         if ((addr >= start) && (addr < end))
> >                 return 1;
> >
> >       if (arch_is_kernel_data(addr))
> >               return 1;
> >
> > We could implement arch_is_kernel_data to fixup it.
> >
> > Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> > Signed-off-by: Guo Ren <[e-mail]>
> > Reported-by: Aurelien Jarno <[e-mail]>
> > Cc: Palmer Dabbelt <[e-mail]>
> > Cc: Atish Patra <[e-mail]>
> > Cc: Andreas Schwab <[e-mail]>
> > Cc: Aurelien Jarno <[e-mail]>
> > ---
> >  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
> >  arch/riscv/kernel/setup.c         |  9 +++++++++
> >  2 files changed, 29 insertions(+)
> >  create mode 100644 arch/riscv/include/asm/sections.h
> >
> > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> > new file mode 100644
> > index 00000000..2317b9e
> > --- /dev/null
> > +++ b/arch/riscv/include/asm/sections.h
> > @@ -0,0 +1,20 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +#ifndef _ASM_RISCV_SECTIONS_H
> > +#define _ASM_RISCV_SECTIONS_H
> > +
> > +#define arch_is_kernel_data arch_is_kernel_data
> > +
> > +#include <asm-generic/sections.h>
> > +
> > +extern bool init_mem_is_free;
> > +
> > +static inline int arch_is_kernel_data(unsigned long addr)
> > +{
> > +     if (init_mem_is_free)
> > +             return 0;
> > +
> > +     return addr >= (unsigned long)__init_begin &&
> > +             addr < (unsigned long)__init_end;
> > +}
> > +#endif /* _ASM_RISCV_SECTIONS_H */
> > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > index 2c6dd32..9ebd5eb4 100644
> > --- a/arch/riscv/kernel/setup.c
> > +++ b/arch/riscv/kernel/setup.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/sched/task.h>
> >  #include <linux/swiotlb.h>
> >  #include <linux/smp.h>
> > +#include <linux/poison.h>
> >
> >  #include <asm/cpu_ops.h>
> >  #include <asm/setup.h>
> > @@ -112,3 +113,11 @@ static int __init topology_init(void)
> >       return 0;
> >  }
> >  subsys_initcall(topology_init);
> > +
> > +bool init_mem_is_free = false;
> > +
> > +void free_initmem(void)
> > +{
> > +     free_initmem_default(POISON_FREE_INITMEM);
> > +     init_mem_is_free = true;
> > +}
>
> I'm a bit confused as to what you're trying to do here.  Yesterday I got
> another version of this patch set that moves init data around, today a
> different one.  Yesterday's is tested and simpler, and given it's so late in
> the process I'm inclined to take that as I don't want to break anything.
>
> Right now I have
>
> 84814460eef9 ("riscv: Fixup bootup failure with HARDENED_USERCOPY")
> a78c6f5956a9 ("RISC-V: Make sure memblock reserves the memory containing DT")
> 549738f15da0 ("Linux 5.9-rc8")
>
> Unless there's some functional bug, that's what I'm going to send out for 5.9
> -- I'm not all that worried about lacking the ability to free init data.  The
> above seems like fine 5.10 material.
>
> Let me know if I'm missing something here.
84814460eef9 could resolve the problem and Atish ask for any other
idea? So It's another choice, I forgot RFC in prefix.

6184358da0004c8fd940afda6c0a0fa4027dc911("riscv: Fixup static_obj()
fail") is a sloppy patch that introduces another problem. Sorry about
that.

Atish Patra Oct. 9, 2020, 9:16 p.m. UTC | #6

On Thu, Oct 8, 2020 at 6:53 PM Guo Ren <[e-mail]> wrote:
>
> On Thu, Oct 8, 2020 at 11:54 AM Palmer Dabbelt <[e-mail]> wrote:
> >
> > On Wed, 07 Oct 2020 08:08:33 PDT (-0700), [e-mail] wrote:
> > > From: Guo Ren <[e-mail]>
> > >
> > > v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
> > > been reverted.
> > >
> > > When enable LOCKDEP, static_obj() will cause error:
> > >
> > > [    0.067192] INFO: trying to register non-static key.
> > > [    0.067325] the code is fine but needs lockdep annotation.
> > > [    0.067449] turning off the locking correctness validator.
> > > [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
> > > [    0.067945] Call Trace:
> > > [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
> > > [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
> > > [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
> > > [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
> > > [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
> > > [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
> > > [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
> > > [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
> > > [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
> > > [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
> > > [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
> > > [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
> > >
> > > Because some __initdata static variables is before _stext:
> > >
> > > static int static_obj(const void *obj)
> > > {
> > >         unsigned long start = (unsigned long) &_stext,
> > >                       end   = (unsigned long) &_end,
> > >                       addr  = (unsigned long) obj;
> > >
> > >         /*
> > >          * static variable?
> > >          */
> > >         if ((addr >= start) && (addr < end))
> > >                 return 1;
> > >
> > >       if (arch_is_kernel_data(addr))
> > >               return 1;
> > >
> > > We could implement arch_is_kernel_data to fixup it.
> > >
> > > Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
> > > Signed-off-by: Guo Ren <[e-mail]>
> > > Reported-by: Aurelien Jarno <[e-mail]>
> > > Cc: Palmer Dabbelt <[e-mail]>
> > > Cc: Atish Patra <[e-mail]>
> > > Cc: Andreas Schwab <[e-mail]>
> > > Cc: Aurelien Jarno <[e-mail]>
> > > ---
> > >  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
> > >  arch/riscv/kernel/setup.c         |  9 +++++++++
> > >  2 files changed, 29 insertions(+)
> > >  create mode 100644 arch/riscv/include/asm/sections.h
> > >
> > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
> > > new file mode 100644
> > > index 00000000..2317b9e
> > > --- /dev/null
> > > +++ b/arch/riscv/include/asm/sections.h
> > > @@ -0,0 +1,20 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +
> > > +#ifndef _ASM_RISCV_SECTIONS_H
> > > +#define _ASM_RISCV_SECTIONS_H
> > > +
> > > +#define arch_is_kernel_data arch_is_kernel_data
> > > +
> > > +#include <asm-generic/sections.h>
> > > +
> > > +extern bool init_mem_is_free;
> > > +
> > > +static inline int arch_is_kernel_data(unsigned long addr)
> > > +{
> > > +     if (init_mem_is_free)
> > > +             return 0;
> > > +
> > > +     return addr >= (unsigned long)__init_begin &&
> > > +             addr < (unsigned long)__init_end;
> > > +}
> > > +#endif /* _ASM_RISCV_SECTIONS_H */
> > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > > index 2c6dd32..9ebd5eb4 100644
> > > --- a/arch/riscv/kernel/setup.c
> > > +++ b/arch/riscv/kernel/setup.c
> > > @@ -17,6 +17,7 @@
> > >  #include <linux/sched/task.h>
> > >  #include <linux/swiotlb.h>
> > >  #include <linux/smp.h>
> > > +#include <linux/poison.h>
> > >
> > >  #include <asm/cpu_ops.h>
> > >  #include <asm/setup.h>
> > > @@ -112,3 +113,11 @@ static int __init topology_init(void)
> > >       return 0;
> > >  }
> > >  subsys_initcall(topology_init);
> > > +
> > > +bool init_mem_is_free = false;
> > > +
> > > +void free_initmem(void)
> > > +{
> > > +     free_initmem_default(POISON_FREE_INITMEM);
> > > +     init_mem_is_free = true;
> > > +}
> >
> > I'm a bit confused as to what you're trying to do here.  Yesterday I got
> > another version of this patch set that moves init data around, today a
> > different one.  Yesterday's is tested and simpler, and given it's so late in
> > the process I'm inclined to take that as I don't want to break anything.
> >
> > Right now I have
> >
> > 84814460eef9 ("riscv: Fixup bootup failure with HARDENED_USERCOPY")
> > a78c6f5956a9 ("RISC-V: Make sure memblock reserves the memory containing DT")
> > 549738f15da0 ("Linux 5.9-rc8")
> >
> > Unless there's some functional bug, that's what I'm going to send out for 5.9
> > -- I'm not all that worried about lacking the ability to free init data.  The
> > above seems like fine 5.10 material.
> >
> > Let me know if I'm missing something here.
> 84814460eef9 could resolve the problem and Atish ask for any other
> idea? So It's another choice, I forgot RFC in prefix.
>

I prefer this fix as it is cleaner and doesn't waste memory. I have
sent another series
on top of this fix, that addresses the init section protections we
talked about. All of these are definitely
next merge window material.

> 6184358da0004c8fd940afda6c0a0fa4027dc911("riscv: Fixup static_obj()
> fail") is a sloppy patch that introduces another problem. Sorry about
> that.
>
> --
> Best Regards
>  Guo Ren
>
> ML: https://lore.kernel.org/linux-csky/

Palmer Dabbelt Oct. 9, 2020, 9:23 p.m. UTC | #7

On Fri, 09 Oct 2020 14:16:00 PDT (-0700), [e-mail] wrote:
> On Thu, Oct 8, 2020 at 6:53 PM Guo Ren <[e-mail]> wrote:
>>
>> On Thu, Oct 8, 2020 at 11:54 AM Palmer Dabbelt <[e-mail]> wrote:
>> >
>> > On Wed, 07 Oct 2020 08:08:33 PDT (-0700), [e-mail] wrote:
>> > > From: Guo Ren <[e-mail]>
>> > >
>> > > v1 is commit: 6184358da0004c8fd940afda6c0a0fa4027dc911 which has
>> > > been reverted.
>> > >
>> > > When enable LOCKDEP, static_obj() will cause error:
>> > >
>> > > [    0.067192] INFO: trying to register non-static key.
>> > > [    0.067325] the code is fine but needs lockdep annotation.
>> > > [    0.067449] turning off the locking correctness validator.
>> > > [    0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
>> > > [    0.067945] Call Trace:
>> > > [    0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
>> > > [    0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
>> > > [    0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
>> > > [    0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
>> > > [    0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
>> > > [    0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
>> > > [    0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
>> > > [    0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
>> > > [    0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
>> > > [    0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
>> > > [    0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
>> > > [    0.069953] [<ffffffe000001092>] 0xffffffe000001092
>> > >
>> > > Because some __initdata static variables is before _stext:
>> > >
>> > > static int static_obj(const void *obj)
>> > > {
>> > >         unsigned long start = (unsigned long) &_stext,
>> > >                       end   = (unsigned long) &_end,
>> > >                       addr  = (unsigned long) obj;
>> > >
>> > >         /*
>> > >          * static variable?
>> > >          */
>> > >         if ((addr >= start) && (addr < end))
>> > >                 return 1;
>> > >
>> > >       if (arch_is_kernel_data(addr))
>> > >               return 1;
>> > >
>> > > We could implement arch_is_kernel_data to fixup it.
>> > >
>> > > Link: https://lore.kernel.org/linux-riscv/[e-mail]/T/#t
>> > > Signed-off-by: Guo Ren <[e-mail]>
>> > > Reported-by: Aurelien Jarno <[e-mail]>
>> > > Cc: Palmer Dabbelt <[e-mail]>
>> > > Cc: Atish Patra <[e-mail]>
>> > > Cc: Andreas Schwab <[e-mail]>
>> > > Cc: Aurelien Jarno <[e-mail]>
>> > > ---
>> > >  arch/riscv/include/asm/sections.h | 20 ++++++++++++++++++++
>> > >  arch/riscv/kernel/setup.c         |  9 +++++++++
>> > >  2 files changed, 29 insertions(+)
>> > >  create mode 100644 arch/riscv/include/asm/sections.h
>> > >
>> > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
>> > > new file mode 100644
>> > > index 00000000..2317b9e
>> > > --- /dev/null
>> > > +++ b/arch/riscv/include/asm/sections.h
>> > > @@ -0,0 +1,20 @@
>> > > +/* SPDX-License-Identifier: GPL-2.0-only */
>> > > +
>> > > +#ifndef _ASM_RISCV_SECTIONS_H
>> > > +#define _ASM_RISCV_SECTIONS_H
>> > > +
>> > > +#define arch_is_kernel_data arch_is_kernel_data
>> > > +
>> > > +#include <asm-generic/sections.h>
>> > > +
>> > > +extern bool init_mem_is_free;
>> > > +
>> > > +static inline int arch_is_kernel_data(unsigned long addr)
>> > > +{
>> > > +     if (init_mem_is_free)
>> > > +             return 0;
>> > > +
>> > > +     return addr >= (unsigned long)__init_begin &&
>> > > +             addr < (unsigned long)__init_end;
>> > > +}
>> > > +#endif /* _ASM_RISCV_SECTIONS_H */
>> > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
>> > > index 2c6dd32..9ebd5eb4 100644
>> > > --- a/arch/riscv/kernel/setup.c
>> > > +++ b/arch/riscv/kernel/setup.c
>> > > @@ -17,6 +17,7 @@
>> > >  #include <linux/sched/task.h>
>> > >  #include <linux/swiotlb.h>
>> > >  #include <linux/smp.h>
>> > > +#include <linux/poison.h>
>> > >
>> > >  #include <asm/cpu_ops.h>
>> > >  #include <asm/setup.h>
>> > > @@ -112,3 +113,11 @@ static int __init topology_init(void)
>> > >       return 0;
>> > >  }
>> > >  subsys_initcall(topology_init);
>> > > +
>> > > +bool init_mem_is_free = false;
>> > > +
>> > > +void free_initmem(void)
>> > > +{
>> > > +     free_initmem_default(POISON_FREE_INITMEM);
>> > > +     init_mem_is_free = true;
>> > > +}
>> >
>> > I'm a bit confused as to what you're trying to do here.  Yesterday I got
>> > another version of this patch set that moves init data around, today a
>> > different one.  Yesterday's is tested and simpler, and given it's so late in
>> > the process I'm inclined to take that as I don't want to break anything.
>> >
>> > Right now I have
>> >
>> > 84814460eef9 ("riscv: Fixup bootup failure with HARDENED_USERCOPY")
>> > a78c6f5956a9 ("RISC-V: Make sure memblock reserves the memory containing DT")
>> > 549738f15da0 ("Linux 5.9-rc8")
>> >
>> > Unless there's some functional bug, that's what I'm going to send out for 5.9
>> > -- I'm not all that worried about lacking the ability to free init data.  The
>> > above seems like fine 5.10 material.
>> >
>> > Let me know if I'm missing something here.
>> 84814460eef9 could resolve the problem and Atish ask for any other
>> idea? So It's another choice, I forgot RFC in prefix.
>>
>
> I prefer this fix as it is cleaner and doesn't waste memory. I have
> sent another series
> on top of this fix, that addresses the init section protections we
> talked about. All of these are definitely
> next merge window material.

Thanks, I'll take a look.

>
>> 6184358da0004c8fd940afda6c0a0fa4027dc911("riscv: Fixup static_obj()
>> fail") is a sloppy patch that introduces another problem. Sorry about
>> that.
>>
>> --
>> Best Regards
>>  Guo Ren
>>
>> ML: https://lore.kernel.org/linux-csky/

Patch

diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
new file mode 100644
index 00000000..2317b9e
--- /dev/null
+++ b/arch/riscv/include/asm/sections.h
@@ -0,0 +1,20 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _ASM_RISCV_SECTIONS_H
+#define _ASM_RISCV_SECTIONS_H
+
+#define arch_is_kernel_data arch_is_kernel_data
+
+#include <asm-generic/sections.h>
+
+extern bool init_mem_is_free;
+
+static inline int arch_is_kernel_data(unsigned long addr)
+{
+	if (init_mem_is_free)
+		return 0;
+
+	return addr >= (unsigned long)__init_begin &&
+		addr < (unsigned long)__init_end;
+}
+#endif /* _ASM_RISCV_SECTIONS_H */
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 2c6dd32..9ebd5eb4 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -17,6 +17,7 @@ 
 #include <linux/sched/task.h>
 #include <linux/swiotlb.h>
 #include <linux/smp.h>
+#include <linux/poison.h>
 
 #include <asm/cpu_ops.h>
 #include <asm/setup.h>
@@ -112,3 +113,11 @@  static int __init topology_init(void)
 	return 0;
 }
 subsys_initcall(topology_init);
+
+bool init_mem_is_free = false;
+
+void free_initmem(void)
+{
+	free_initmem_default(POISON_FREE_INITMEM);
+	init_mem_is_free = true;
+}