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    SubjectRe: [PATCH] arm64: fix build error when use rodata_enabled
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    Hello,

    On 1/5/22 8:37 AM, AliOS system security wrote:
    > rodata_enabled should be used when CONFIG_STRICT_KERNEL_RWX
    > or CONFIG_STRICT_MODULE_RWX is selected

    Both these configs get selected invariably with CONFIG_ARM64 in the
    platform config file (arch/arm64/Kconfig). I guess there can not be
    any such situation, where both configs will be missing/not selected
    given ARCH_OPTIONAL_KERNEL_RWX[or _DEFAULT] is not enabled on arm64.

    config ARM64
    def_bool y
    select ACPI_CCA_REQUIRED if ACPI
    .....
    select ARCH_HAS_STRICT_KERNEL_RWX
    select ARCH_HAS_STRICT_MODULE_RWX
    .....

    Hence for all practical purpose, rodata_enabled could be considered
    always available. I am sure there other similar situations as well,
    where code elements are not wrapped around if the config option is
    always present.

    >
    > Signed-off-by: AliOS system security <alios_sys_security@linux.alibaba.com>

    Also please refer Documentation/process/submitting-patches.rst for
    the rules regarding names, that can be used for a commit sign off.

    ------------------------------------------------------------------------
    then you just add a line saying::

    Signed-off-by: Random J Developer <random@developer.example.org>

    using your real name (sorry, no pseudonyms or anonymous contributions.)
    ------------------------------------------------------------------------

    - Anshuman

    > ---
    > arch/arm64/mm/mmu.c | 14 ++++++++++++--
    > 1 file changed, 12 insertions(+), 2 deletions(-)
    >
    > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
    > index acfae9b..47f8754 100644
    > --- a/arch/arm64/mm/mmu.c
    > +++ b/arch/arm64/mm/mmu.c
    > @@ -596,6 +596,7 @@ static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
    > vm_area_add_early(vma);
    > }
    >
    > +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
    > static int __init parse_rodata(char *arg)
    > {
    > int ret = strtobool(arg, &rodata_enabled);
    > @@ -613,11 +614,16 @@ static int __init parse_rodata(char *arg)
    > return 0;
    > }
    > early_param("rodata", parse_rodata);
    > +#endif
    >
    > #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
    > static int __init map_entry_trampoline(void)
    > {
    > - pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
    > + pgprot_t prot = PAGE_KERNEL_EXEC;
    > +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
    > + if (rodata_enabled)
    > + prot = PAGE_KERNEL_ROX;
    > +#endif
    > phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start);
    >
    > /* The trampoline is always mapped and can therefore be global */
    > @@ -672,7 +678,11 @@ static void __init map_kernel(pgd_t *pgdp)
    > * mapping to install SW breakpoints. Allow this (only) when
    > * explicitly requested with rodata=off.
    > */
    > - pgprot_t text_prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
    > + pgprot_t text_prot = PAGE_KERNEL_EXEC;
    > +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
    > + if (rodata_enabled)
    > + text_prot = PAGE_KERNEL_ROX;
    > +#endif
    >
    > /*
    > * If we have a CPU that supports BTI and a kernel built for
    >

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