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) {
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
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