| Message ID | 20200601050656.826296-1-anup.patel@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] RISC-V: Don't mark init section as non-executable | expand |
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>
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>
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) {
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(-)