riscv: mm: add support for CONFIG_DEBUG_VIRTUAL (6435f773) · Commits · 戴 / test

This patch implements CONFIG_DEBUG_VIRTUAL to do additional checks on virt_to_phys and __pa_symbol calls. virt_to_phys used for linear mapping check, and __pa_symbol used for kernel symbol check. In current RISC-V, kernel image maps to linear mapping area. If CONFIG_DEBUG_VIRTUAL is disable, these two functions calculate the offset on the address feded directly without any checks. The result of test_debug_virtual as follows: [ 0.358456] ------------[ cut here ]------------ [ 0.358738] virt_to_phys used for non-linear address: (____ptrval____) (0xffffffd000000000) [ 0.359174] WARNING: CPU: 0 PID: 1 at arch/riscv/mm/physaddr.c:16 __virt_to_phys+0x3c/0x50 [ 0.359409] Modules linked in: [ 0.359630] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc3-00002-g5133c5c0ca13 #57 [ 0.359861] epc: ffffffe000253d1a ra : ffffffe000253d1a sp : ffffffe03aa87da0 [ 0.360019] gp : ffffffe000ae03b0 tp : ffffffe03aa88000 t0 : ffffffe000af2660 [ 0.360175] t1 : 0000000000000064 t2 : 00000000000000b7 s0 : ffffffe03aa87dc0 [ 0.360330] s1 : ffffffd000000000 a0 : 000000000000004f a1 : 0000000000000000 [ 0.360492] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffe000a84358 [ 0.360672] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000000000 [ 0.360876] s2 : ffffffe000ae0600 s3 : ffffffe00000fc7c s4 : ffffffe0000224b0 [ 0.361067] s5 : ffffffe000030890 s6 : ffffffe000022470 s7 : 0000000000000008 [ 0.361267] s8 : ffffffe0000002c4 s9 : ffffffe000ae0640 s10: ffffffe000ae0630 [ 0.361453] s11: 0000000000000000 t3 : 0000000000000000 t4 : 000000000001e6d0 [ 0.361636] t5 : ffffffe000ae0a18 t6 : ffffffe000aee54e [ 0.361806] status: 0000000000000120 badaddr: 0000000000000000 cause: 0000000000000003 [ 0.362056] ---[ end trace aec0bf78d4978122 ]--- [ 0.362404] PA: 0xfffffff080200000 for VA: 0xffffffd000000000 [ 0.362607] PA: 0x00000000baddd2d0 for VA: 0xffffffe03abdd2d0 Signed-off-by:

Zong Li <zong.li@sifive.com> Reviewed-by:

Paul Walmsley <paul.walmsley@sifive.com> Tested-by:

Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by:

Palmer Dabbelt <palmerdabbelt@google.com>

arch/riscv/Kconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -55,6 +55,7 @@ config RISCV
		select GENERIC_ARCH_TOPOLOGY if SMP
		select ARCH_HAS_PTE_SPECIAL
		select ARCH_HAS_MMIOWB
		select ARCH_HAS_DEBUG_VIRTUAL
		select HAVE_EBPF_JIT if 64BIT
		select EDAC_SUPPORT
		select ARCH_HAS_GIGANTIC_PAGE

arch/riscv/include/asm/page.h

+14 −2

Original line number	Diff line number	Diff line
		@@ -100,8 +100,20 @@ extern unsigned long pfn_base;
		extern unsigned long max_low_pfn;
		extern unsigned long min_low_pfn;

		#define __pa(x) ((unsigned long)(x) - va_pa_offset)
		#define __va(x) ((void *)((unsigned long) (x) + va_pa_offset))
		#define __pa_to_va_nodebug(x) ((void *)((unsigned long) (x) + va_pa_offset))
		#define __va_to_pa_nodebug(x) ((unsigned long)(x) - va_pa_offset)

		#ifdef CONFIG_DEBUG_VIRTUAL
		extern phys_addr_t __virt_to_phys(unsigned long x);
		extern phys_addr_t __phys_addr_symbol(unsigned long x);
		#else
		#define __virt_to_phys(x) __va_to_pa_nodebug(x)
		#define __phys_addr_symbol(x) __va_to_pa_nodebug(x)
		#endif /* CONFIG_DEBUG_VIRTUAL */

		#define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
		#define __pa(x) __virt_to_phys((unsigned long)(x))
		#define __va(x) ((void *)__pa_to_va_nodebug((phys_addr_t)(x)))

		#define phys_to_pfn(phys) (PFN_DOWN(phys))
		#define pfn_to_phys(pfn) (PFN_PHYS(pfn))

arch/riscv/mm/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -21,3 +21,5 @@ ifdef CONFIG_KASAN
		KASAN_SANITIZE_kasan_init.o := n
		KASAN_SANITIZE_init.o := n
		endif

		obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o

arch/riscv/mm/physaddr.c

0 → 100644

+37 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0

		#include <linux/types.h>
		#include <linux/mmdebug.h>
		#include <linux/mm.h>
		#include <asm/page.h>
		#include <asm/sections.h>

		phys_addr_t __virt_to_phys(unsigned long x)
		{
		phys_addr_t y = x - PAGE_OFFSET;

		/*
		* Boundary checking aginst the kernel linear mapping space.
		*/
		WARN(y >= KERN_VIRT_SIZE,
		"virt_to_phys used for non-linear address: %pK (%pS)\n",
		(void )x, (void )x);

		return __va_to_pa_nodebug(x);
		}
		EXPORT_SYMBOL(__virt_to_phys);

		phys_addr_t __phys_addr_symbol(unsigned long x)
		{
		unsigned long kernel_start = (unsigned long)PAGE_OFFSET;
		unsigned long kernel_end = (unsigned long)_end;

		/*
		* Boundary checking aginst the kernel image mapping.
		* __pa_symbol should only be used on kernel symbol addresses.
		*/
		VIRTUAL_BUG_ON(x < kernel_start \|\| x > kernel_end);

		return __va_to_pa_nodebug(x);
		}
		EXPORT_SYMBOL(__phys_addr_symbol);

Admin message