Re: [PATCH] MIPS: Fixed __debug_virt_addr_valid()

From: Florian Fainelli
Date: Mon Jul 11 2022 - 20:02:58 EST

On 7/11/2022 4:29 AM, Serge Semin wrote:
On Mon, Jul 11, 2022 at 01:27:40PM +0200, Thomas Bogendoerfer wrote:
On Mon, Jul 11, 2022 at 01:40:52PM +0300, Serge Semin wrote:
On Mon, Jul 11, 2022 at 10:38:48AM +0200, Thomas Bogendoerfer wrote:
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@xxxxxxxxx>
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)
return true;
- return false;
+ return KSEGX(x) < KSEG2;
phys_addr_t __virt_to_phys(volatile const void *x)

applied to mips-next.

Are you sure it was ready to be applied?

your comment sounded like optimizing, which can be done later on, so
I assumed it ready.

What about Malta and EVA?

Sergey's comment definitively need to be addressed, and I would not see the point in making an incremental change to a wrong fix. Can you drop that patch for now? Thanks!