Commit 6b60a128 authored Mar 23, 2026 by Vivian Wang Committed by Paul Walmsley Apr 04, 2026

riscv: patch: Avoid early phys_to_page()



Similarly to commit 8d09e2d5 ("arm64: patching: avoid early
page_to_phys()"), avoid using phys_to_page() for the kernel address case
in patch_map().

Since this is called from apply_boot_alternatives() in setup_arch(), and
commit 4267739c ("arch, mm: consolidate initialization of SPARSE
memory model") has moved sparse_init() to after setup_arch(),
phys_to_page() is not available there yet, and it panics on boot with
SPARSEMEM on RV32, which does not use SPARSEMEM_VMEMMAP.

Reported-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Closes: https://lore.kernel.org/r/20260223144108-dcace0b9-02e8-4b67-a7ce-f263bed36f26@linutronix.de/


Fixes: 4267739c ("arch, mm: consolidate initialization of SPARSE memory model")
Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20260310-riscv-sparsemem-alternatives-fix-v1-1-659d5dd257e2@iscas.ac.cn


[pjw@kernel.org: fix the subject line to align with the patch description]
Signed-off-by: Paul Walmsley <pjw@kernel.org>

parent 834911eb

arch/riscv/kernel/patch.c

+11 −10

Original line number	Diff line number	Diff line
		@@ -42,19 +42,20 @@ static inline bool is_kernel_exittext(uintptr_t addr)
		static __always_inline void patch_map(void addr, const unsigned int fixmap)
		{
		uintptr_t uintaddr = (uintptr_t) addr;
		struct page *page;
		phys_addr_t phys;

		if (core_kernel_text(uintaddr) \|\| is_kernel_exittext(uintaddr))
		page = phys_to_page(__pa_symbol(addr));
		else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
		page = vmalloc_to_page(addr);
		else
		return addr;
		if (core_kernel_text(uintaddr) \|\| is_kernel_exittext(uintaddr)) {
		phys = __pa_symbol(addr);
		} else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) {
		struct page *page = vmalloc_to_page(addr);

		BUG_ON(!page);
		phys = page_to_phys(page) + offset_in_page(addr);
		} else {
		return addr;
		}

		return (void *)set_fixmap_offset(fixmap, page_to_phys(page) +
		offset_in_page(addr));
		return (void *)set_fixmap_offset(fixmap, phys);
		}

		static void patch_unmap(int fixmap)