Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fix from Catalin Marinas:
"Move the arm64_use_ng_mappings variable from the .bss to the .data
section as it is accessed very early during boot with the MMU off and
before the .bss has been initialised.
This could lead to incorrect idmap page table"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: cpufeature: Move arm64_use_ng_mappings to the .data section to prevent wrong idmap generation
+8
-1
+8
-1
arch/arm64/kernel/cpufeature.c
+8
-1
arch/arm64/kernel/cpufeature.c
···
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DECLARE_BITMAP(boot_cpucaps, ARM64_NCAPS);
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-
bool arm64_use_ng_mappings = false;
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/*
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* arm64_use_ng_mappings must be placed in the .data section, otherwise it
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* ends up in the .bss section where it is initialized in early_map_kernel()
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* after the MMU (with the idmap) was enabled. create_init_idmap() - which
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* runs before early_map_kernel() and reads the variable via PTE_MAYBE_NG -
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* may end up generating an incorrect idmap page table attributes.
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*/
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bool arm64_use_ng_mappings __read_mostly = false;
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EXPORT_SYMBOL(arm64_use_ng_mappings);
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DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;