* [PATCH v2] RISC-V: Don't mark init section as non-executable
@ 2020-06-01 5:06 ` Anup Patel
0 siblings, 0 replies; 6+ messages in thread
From: Anup Patel @ 2020-06-01 5:06 UTC (permalink / raw)
To: Palmer Dabbelt, Paul Walmsley, Albert Ou
Cc: Atish Patra, Alistair Francis, Anup Patel, linux-riscv,
linux-kernel, Anup Patel, stable
The head text section (i.e. _start, secondary_start_sbi, etc) and the
init section fall under same page table level-1 mapping.
Currently, the runtime CPU hotplug is broken because we are marking
init section as non-executable which in-turn marks head text section
as non-executable.
Further investigating other architectures, it seems marking the init
section as non-executable is redundant because the init section pages
are anyway poisoned and freed.
To fix broken runtime CPU hotplug, we simply remove the code marking
the init section as non-executable.
Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
Changes since v1:
- Updated free_initmem() is same as generic free_initmem() defined in
init/main.c so we completely remove free_initmem() from arch/riscv
---
arch/riscv/mm/init.c | 11 -----------
1 file changed, 11 deletions(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 736de6c8739f..fdc772f57edc 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
local_flush_tlb_all();
}
-
-void free_initmem(void)
-{
- unsigned long init_begin = (unsigned long)__init_begin;
- unsigned long init_end = (unsigned long)__init_end;
-
- /* Make the region as non-execuatble. */
- set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
- free_initmem_default(POISON_FREE_INITMEM);
-}
-
#else
asmlinkage void __init setup_vm(uintptr_t dtb_pa)
{
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2] RISC-V: Don't mark init section as non-executable
@ 2020-06-01 5:06 ` Anup Patel
0 siblings, 0 replies; 6+ messages in thread
From: Anup Patel @ 2020-06-01 5:06 UTC (permalink / raw)
To: Palmer Dabbelt, Paul Walmsley, Albert Ou
Cc: Anup Patel, Anup Patel, linux-kernel, stable, Atish Patra,
Alistair Francis, linux-riscv
The head text section (i.e. _start, secondary_start_sbi, etc) and the
init section fall under same page table level-1 mapping.
Currently, the runtime CPU hotplug is broken because we are marking
init section as non-executable which in-turn marks head text section
as non-executable.
Further investigating other architectures, it seems marking the init
section as non-executable is redundant because the init section pages
are anyway poisoned and freed.
To fix broken runtime CPU hotplug, we simply remove the code marking
the init section as non-executable.
Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
Changes since v1:
- Updated free_initmem() is same as generic free_initmem() defined in
init/main.c so we completely remove free_initmem() from arch/riscv
---
arch/riscv/mm/init.c | 11 -----------
1 file changed, 11 deletions(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 736de6c8739f..fdc772f57edc 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
local_flush_tlb_all();
}
-
-void free_initmem(void)
-{
- unsigned long init_begin = (unsigned long)__init_begin;
- unsigned long init_end = (unsigned long)__init_end;
-
- /* Make the region as non-execuatble. */
- set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
- free_initmem_default(POISON_FREE_INITMEM);
-}
-
#else
asmlinkage void __init setup_vm(uintptr_t dtb_pa)
{
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2] RISC-V: Don't mark init section as non-executable
2020-06-01 5:06 ` Anup Patel
@ 2020-06-01 7:28 ` Zong Li
-1 siblings, 0 replies; 6+ messages in thread
From: Zong Li @ 2020-06-01 7:28 UTC (permalink / raw)
To: Anup Patel
Cc: Palmer Dabbelt, Paul Walmsley, Albert Ou, Anup Patel,
Linux Kernel Mailing List, stable, Atish Patra, Alistair Francis,
linux-riscv
Anup Patel <anup.patel@wdc.com> 於 2020年6月1日 週一 下午1:07寫道：
>
> The head text section (i.e. _start, secondary_start_sbi, etc) and the
> init section fall under same page table level-1 mapping.
>
> Currently, the runtime CPU hotplug is broken because we are marking
> init section as non-executable which in-turn marks head text section
> as non-executable.
>
> Further investigating other architectures, it seems marking the init
> section as non-executable is redundant because the init section pages
> are anyway poisoned and freed.
>
> To fix broken runtime CPU hotplug, we simply remove the code marking
> the init section as non-executable.
>
> Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
> Changes since v1:
> - Updated free_initmem() is same as generic free_initmem() defined in
> init/main.c so we completely remove free_initmem() from arch/riscv
> ---
> arch/riscv/mm/init.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 736de6c8739f..fdc772f57edc 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
> csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
> local_flush_tlb_all();
> }
> -
> -void free_initmem(void)
> -{
> - unsigned long init_begin = (unsigned long)__init_begin;
> - unsigned long init_end = (unsigned long)__init_end;
> -
> - /* Make the region as non-execuatble. */
> - set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
> - free_initmem_default(POISON_FREE_INITMEM);
> -}
> -
> #else
> asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> {
> --
> 2.25.1
>
>
It looks good to me.
Reviewed-by: Zong Li <zong.li@sifive.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] RISC-V: Don't mark init section as non-executable
@ 2020-06-01 7:28 ` Zong Li
0 siblings, 0 replies; 6+ messages in thread
From: Zong Li @ 2020-06-01 7:28 UTC (permalink / raw)
To: Anup Patel
Cc: Albert Ou, Anup Patel, Linux Kernel Mailing List, stable,
Atish Patra, Palmer Dabbelt, Paul Walmsley, Alistair Francis,
linux-riscv
Anup Patel <anup.patel@wdc.com> 於 2020年6月1日 週一 下午1:07寫道：
>
> The head text section (i.e. _start, secondary_start_sbi, etc) and the
> init section fall under same page table level-1 mapping.
>
> Currently, the runtime CPU hotplug is broken because we are marking
> init section as non-executable which in-turn marks head text section
> as non-executable.
>
> Further investigating other architectures, it seems marking the init
> section as non-executable is redundant because the init section pages
> are anyway poisoned and freed.
>
> To fix broken runtime CPU hotplug, we simply remove the code marking
> the init section as non-executable.
>
> Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
> Changes since v1:
> - Updated free_initmem() is same as generic free_initmem() defined in
> init/main.c so we completely remove free_initmem() from arch/riscv
> ---
> arch/riscv/mm/init.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 736de6c8739f..fdc772f57edc 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
> csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
> local_flush_tlb_all();
> }
> -
> -void free_initmem(void)
> -{
> - unsigned long init_begin = (unsigned long)__init_begin;
> - unsigned long init_end = (unsigned long)__init_end;
> -
> - /* Make the region as non-execuatble. */
> - set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
> - free_initmem_default(POISON_FREE_INITMEM);
> -}
> -
> #else
> asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> {
> --
> 2.25.1
>
>
It looks good to me.
Reviewed-by: Zong Li <zong.li@sifive.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] RISC-V: Don't mark init section as non-executable
2020-06-01 5:06 ` Anup Patel
@ 2020-06-01 18:23 ` Atish Patra
-1 siblings, 0 replies; 6+ messages in thread
From: Atish Patra @ 2020-06-01 18:23 UTC (permalink / raw)
To: Anup Patel
Cc: Palmer Dabbelt, Paul Walmsley, Albert Ou, Anup Patel,
linux-kernel@vger.kernel.org List, stable, Atish Patra,
Alistair Francis, linux-riscv
On Sun, May 31, 2020 at 10:07 PM Anup Patel <anup.patel@wdc.com> wrote:
>
> The head text section (i.e. _start, secondary_start_sbi, etc) and the
> init section fall under same page table level-1 mapping.
>
> Currently, the runtime CPU hotplug is broken because we are marking
> init section as non-executable which in-turn marks head text section
> as non-executable.
>
> Further investigating other architectures, it seems marking the init
> section as non-executable is redundant because the init section pages
> are anyway poisoned and freed.
>
> To fix broken runtime CPU hotplug, we simply remove the code marking
> the init section as non-executable.
>
> Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
> Changes since v1:
> - Updated free_initmem() is same as generic free_initmem() defined in
> init/main.c so we completely remove free_initmem() from arch/riscv
> ---
> arch/riscv/mm/init.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 736de6c8739f..fdc772f57edc 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
> csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
> local_flush_tlb_all();
> }
> -
> -void free_initmem(void)
> -{
> - unsigned long init_begin = (unsigned long)__init_begin;
> - unsigned long init_end = (unsigned long)__init_end;
> -
> - /* Make the region as non-execuatble. */
> - set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
> - free_initmem_default(POISON_FREE_INITMEM);
> -}
> -
> #else
> asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> {
> --
> 2.25.1
>
>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
--
Regards,
Atish
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] RISC-V: Don't mark init section as non-executable
@ 2020-06-01 18:23 ` Atish Patra
0 siblings, 0 replies; 6+ messages in thread
From: Atish Patra @ 2020-06-01 18:23 UTC (permalink / raw)
To: Anup Patel
Cc: Albert Ou, Anup Patel, linux-kernel@vger.kernel.org List, stable,
Atish Patra, Palmer Dabbelt, Paul Walmsley, Alistair Francis,
linux-riscv
On Sun, May 31, 2020 at 10:07 PM Anup Patel <anup.patel@wdc.com> wrote:
>
> The head text section (i.e. _start, secondary_start_sbi, etc) and the
> init section fall under same page table level-1 mapping.
>
> Currently, the runtime CPU hotplug is broken because we are marking
> init section as non-executable which in-turn marks head text section
> as non-executable.
>
> Further investigating other architectures, it seems marking the init
> section as non-executable is redundant because the init section pages
> are anyway poisoned and freed.
>
> To fix broken runtime CPU hotplug, we simply remove the code marking
> the init section as non-executable.
>
> Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
> Changes since v1:
> - Updated free_initmem() is same as generic free_initmem() defined in
> init/main.c so we completely remove free_initmem() from arch/riscv
> ---
> arch/riscv/mm/init.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 736de6c8739f..fdc772f57edc 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -479,17 +479,6 @@ static void __init setup_vm_final(void)
> csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
> local_flush_tlb_all();
> }
> -
> -void free_initmem(void)
> -{
> - unsigned long init_begin = (unsigned long)__init_begin;
> - unsigned long init_end = (unsigned long)__init_end;
> -
> - /* Make the region as non-execuatble. */
> - set_memory_nx(init_begin, (init_end - init_begin) >> PAGE_SHIFT);
> - free_initmem_default(POISON_FREE_INITMEM);
> -}
> -
> #else
> asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> {
> --
> 2.25.1
>
>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
--
Regards,
Atish
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-06-01 18:42 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2020-06-01 5:06 [PATCH v2] RISC-V: Don't mark init section as non-executable Anup Patel
2020-06-01 5:06 ` Anup Patel
2020-06-01 7:28 ` Zong Li
2020-06-01 7:28 ` Zong Li
2020-06-01 18:23 ` Atish Patra
2020-06-01 18:23 ` Atish Patra
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