Messages in this thread | | | Date | Fri, 8 Jul 2022 14:58:51 +0300 | From | Serge Semin <> | Subject | Re: [PATCH] MIPS: Fixed __debug_virt_addr_valid() |
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On Thu, Jul 07, 2022 at 02:52:36PM -0700, Florian Fainelli wrote: > It is permissible for kernel code to call virt_to_phys() against virtual > addresses that are in KSEG0 or KSEG1 and we need to be dealing with both > types. Add a final condition that ensures that the virtual address is > below KSEG2. > > Fixes: dfad83cb7193 ("MIPS: Add support for CONFIG_DEBUG_VIRTUAL") > Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> > --- > arch/mips/mm/physaddr.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/mips/mm/physaddr.c b/arch/mips/mm/physaddr.c > index a1ced5e44951..a82f8f57a652 100644 > --- a/arch/mips/mm/physaddr.c > +++ b/arch/mips/mm/physaddr.c > @@ -5,6 +5,7 @@ > #include <linux/mmdebug.h> > #include <linux/mm.h> > > +#include <asm/addrspace.h> > #include <asm/sections.h> > #include <asm/io.h> > #include <asm/page.h> > @@ -30,7 +31,7 @@ static inline bool __debug_virt_addr_valid(unsigned long x) > if (x == MAX_DMA_ADDRESS) > return true; >
> - return false; > + return KSEGX(x) < KSEG2;
With this do we really need the high_memory-based conditionals in this method?
If the line above is the only way to take the uncached segment into account then can we reduce the whole method to: static inline bool __debug_virt_addr_valid { return x >= PAGE_OFFSET && KSEGX(x) < KSEG2; } ?
Though this still may be invalid for EVA systems, like malta (see arch/mips/include/asm/mach-malta/spaces.h).
Note AFAICS if EVA is enabled, highmem is implied to be disabled (see the CPU_MIPS32_3_5_EVA config utilization and HIGHMEM config dependencies). Thus all the memory is supposed to be linearly mapped in that case.
-Sergey
> } > > phys_addr_t __virt_to_phys(volatile const void *x) > -- > 2.25.1 >
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