| Message ID | 20210323222103.34225-1-f.fainelli@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] MIPS: Add support for CONFIG_DEBUG_VIRTUAL | expand |
On Tue, Mar 23, 2021 at 03:20:43PM -0700, Florian Fainelli wrote: > Provide hooks to intercept bad usages of virt_to_phys() and > __pa_symbol() throughout the kernel. To make this possible, we need to > rename the current implement of virt_to_phys() into > __virt_to_phys_nodebug() and wrap it around depending on > CONFIG_DEBUG_VIRTUAL. > > A similar thing is needed for __pa_symbol() which is now aliased to > __phys_addr_symbol() whose implementation is either the direct return of > RELOC_HIDE or goes through the debug version. > > Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> > --- > Changes in v2: > - fixed sparse warning in arch/mips/kernel/vdso.c checkpatch warns about a missing SPDX license in arch/mips/mm/physaddr.c, can you please add one ? And as checkpatch is also unhappy about the volatiles, do we really need them here ? Thomas.
On 3/25/2021 2:57 AM, Thomas Bogendoerfer wrote: > On Tue, Mar 23, 2021 at 03:20:43PM -0700, Florian Fainelli wrote: >> Provide hooks to intercept bad usages of virt_to_phys() and >> __pa_symbol() throughout the kernel. To make this possible, we need to >> rename the current implement of virt_to_phys() into >> __virt_to_phys_nodebug() and wrap it around depending on >> CONFIG_DEBUG_VIRTUAL. >> >> A similar thing is needed for __pa_symbol() which is now aliased to >> __phys_addr_symbol() whose implementation is either the direct return of >> RELOC_HIDE or goes through the debug version. >> >> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> >> --- >> Changes in v2: >> - fixed sparse warning in arch/mips/kernel/vdso.c > > checkpatch warns about a missing SPDX license in arch/mips/mm/physaddr.c, > can you please add one ? Yes. > > And as checkpatch is also unhappy about the volatiles, do we really > need them here ? This is just following the existing prototypes for virt_to_phys() declared in arch/mips/include/asm/io.h. This can be changed to unsigned long if you prefer?
On Fri, Mar 26, 2021 at 10:45:39AM -0700, Florian Fainelli wrote: > > > On 3/25/2021 2:57 AM, Thomas Bogendoerfer wrote: > > On Tue, Mar 23, 2021 at 03:20:43PM -0700, Florian Fainelli wrote: > >> Provide hooks to intercept bad usages of virt_to_phys() and > >> __pa_symbol() throughout the kernel. To make this possible, we need to > >> rename the current implement of virt_to_phys() into > >> __virt_to_phys_nodebug() and wrap it around depending on > >> CONFIG_DEBUG_VIRTUAL. > >> > >> A similar thing is needed for __pa_symbol() which is now aliased to > >> __phys_addr_symbol() whose implementation is either the direct return of > >> RELOC_HIDE or goes through the debug version. > >> > >> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> > >> --- > >> Changes in v2: > >> - fixed sparse warning in arch/mips/kernel/vdso.c > > > > checkpatch warns about a missing SPDX license in arch/mips/mm/physaddr.c, > > can you please add one ? > > Yes. > > > > > And as checkpatch is also unhappy about the volatiles, do we really > > need them here ? > > This is just following the existing prototypes for virt_to_phys() > declared in arch/mips/include/asm/io.h. This can be changed to unsigned > long if you prefer? I just checked other archs and they also use volatile, so nothing to change here. Thomas.
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index d89efba3d8a4..0904d6351808 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -4,6 +4,7 @@ config MIPS default y select ARCH_32BIT_OFF_T if !64BIT select ARCH_BINFMT_ELF_STATE if MIPS_FP_SUPPORT + select ARCH_HAS_DEBUG_VIRTUAL if !64BIT select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_KCOV select ARCH_HAS_PTE_SPECIAL if !(32BIT && CPU_HAS_RIXI) diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 78537aa23500..2c138450ad3b 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -100,11 +100,23 @@ static inline void set_io_port_base(unsigned long base) * almost all conceivable cases a device driver should not be using * this function */ -static inline unsigned long virt_to_phys(volatile const void *address) +static inline unsigned long __virt_to_phys_nodebug(volatile const void *address) { return __pa(address); } +#ifdef CONFIG_DEBUG_VIRTUAL +extern phys_addr_t __virt_to_phys(volatile const void *x); +#else +#define __virt_to_phys(x) __virt_to_phys_nodebug(x) +#endif + +#define virt_to_phys virt_to_phys +static inline phys_addr_t virt_to_phys(const volatile void *x) +{ + return __virt_to_phys(x); +} + /* * phys_to_virt - map physical address to virtual * @address: address to remap diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h index 65acab9c41f9..195ff4e9771f 100644 --- a/arch/mips/include/asm/page.h +++ b/arch/mips/include/asm/page.h @@ -210,9 +210,16 @@ static inline unsigned long ___pa(unsigned long x) * also affect MIPS so we keep this one until GCC 3.x has been retired * before we can apply https://patchwork.linux-mips.org/patch/1541/ */ +#define __pa_symbol_nodebug(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) + +#ifdef CONFIG_DEBUG_VIRTUAL +extern phys_addr_t __phys_addr_symbol(unsigned long x); +#else +#define __phys_addr_symbol(x) __pa_symbol_nodebug(x) +#endif #ifndef __pa_symbol -#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) +#define __pa_symbol(x) __phys_addr_symbol((unsigned long)(x)) #endif #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c index 7d0b91ad2581..e3fd93ca480a 100644 --- a/arch/mips/kernel/vdso.c +++ b/arch/mips/kernel/vdso.c @@ -158,7 +158,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) /* Map GIC user page. */ if (gic_size) { - gic_pfn = virt_to_phys(mips_gic_base + MIPS_GIC_USER_OFS) >> PAGE_SHIFT; + gic_pfn = virt_to_phys((void *)mips_gic_base + MIPS_GIC_USER_OFS) >> PAGE_SHIFT; ret = io_remap_pfn_range(vma, base, gic_pfn, gic_size, pgprot_noncached(vma->vm_page_prot)); diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile index 865926a37775..fa1f729e0700 100644 --- a/arch/mips/mm/Makefile +++ b/arch/mips/mm/Makefile @@ -40,3 +40,5 @@ obj-$(CONFIG_R5000_CPU_SCACHE) += sc-r5k.o obj-$(CONFIG_RM7000_CPU_SCACHE) += sc-rm7k.o obj-$(CONFIG_MIPS_CPU_SCACHE) += sc-mips.o obj-$(CONFIG_SCACHE_DEBUGFS) += sc-debugfs.o + +obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o diff --git a/arch/mips/mm/physaddr.c b/arch/mips/mm/physaddr.c new file mode 100644 index 000000000000..008b524a96b2 --- /dev/null +++ b/arch/mips/mm/physaddr.c @@ -0,0 +1,55 @@ +#include <linux/bug.h> +#include <linux/export.h> +#include <linux/types.h> +#include <linux/mmdebug.h> +#include <linux/mm.h> + +#include <asm/sections.h> +#include <asm/io.h> +#include <asm/page.h> +#include <asm/dma.h> + +static inline bool __debug_virt_addr_valid(unsigned long x) +{ + /* high_memory does not get immediately defined, and there + * are early callers of __pa() against PAGE_OFFSET + */ + if (!high_memory && x >= PAGE_OFFSET) + return true; + + if (high_memory && x >= PAGE_OFFSET && x < (unsigned long)high_memory) + return true; + + /* + * MAX_DMA_ADDRESS is a virtual address that may not correspond to an + * actual physical address. Enough code relies on + * virt_to_phys(MAX_DMA_ADDRESS) that we just need to work around it + * and always return true. + */ + if (x == MAX_DMA_ADDRESS) + return true; + + return false; +} + +phys_addr_t __virt_to_phys(volatile const void *x) +{ + WARN(!__debug_virt_addr_valid((unsigned long)x), + "virt_to_phys used for non-linear address: %pK (%pS)\n", + x, x); + + return __virt_to_phys_nodebug(x); +} +EXPORT_SYMBOL(__virt_to_phys); + +phys_addr_t __phys_addr_symbol(unsigned long x) +{ + /* This is bounds checking against the kernel image only. + * __pa_symbol should only be used on kernel symbol addresses. + */ + VIRTUAL_BUG_ON(x < (unsigned long)_text || + x > (unsigned long)_end); + + return __pa_symbol_nodebug(x); +} +EXPORT_SYMBOL(__phys_addr_symbol);
Provide hooks to intercept bad usages of virt_to_phys() and __pa_symbol() throughout the kernel. To make this possible, we need to rename the current implement of virt_to_phys() into __virt_to_phys_nodebug() and wrap it around depending on CONFIG_DEBUG_VIRTUAL. A similar thing is needed for __pa_symbol() which is now aliased to __phys_addr_symbol() whose implementation is either the direct return of RELOC_HIDE or goes through the debug version. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- Changes in v2: - fixed sparse warning in arch/mips/kernel/vdso.c arch/mips/Kconfig | 1 + arch/mips/include/asm/io.h | 14 ++++++++- arch/mips/include/asm/page.h | 9 +++++- arch/mips/kernel/vdso.c | 2 +- arch/mips/mm/Makefile | 2 ++ arch/mips/mm/physaddr.c | 55 ++++++++++++++++++++++++++++++++++++ 6 files changed, 80 insertions(+), 3 deletions(-) create mode 100644 arch/mips/mm/physaddr.c