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RISC-V: Don't mark init section as non-executable

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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: d27c3c9081 ("riscv: add STRICT_KERNEL_RWX support")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This commit is contained in:
Anup Patel 2020-06-01 10:36:56 +05:30 committed by Palmer Dabbelt
parent e71ee06e3c
commit 4e0f9e3a61
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1 changed files with 0 additions and 11 deletions
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arch/riscv/mm/init.c
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@ -481,17 +481,6 @@ static void __init setup_vm_final(void)
csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE); csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
local_flush_tlb_all(); 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 #else
asmlinkage void __init setup_vm(uintptr_t dtb_pa) asmlinkage void __init setup_vm(uintptr_t dtb_pa)
{ {