On 2021/12/25 19:04, Nicholas Piggin wrote:
Excerpts from Kefeng Wang's message of December 25, 2021 12:05 pm:
...
Can you try that ?
#define virt_addr_valid(kaddr) ((kaddr & PAGE_OFFSET) == PAGE_OFFSET &&
pfn_valid(virt_to_pfn(kaddr)))
I got this commit,
commit 4dd7554a6456d124c85e0a4ad156625b71390b5c
Author: Nicholas Piggin <npiggin@xxxxxxxxx>
Date: Wed Jul 24 18:46:37 2019 +1000
powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses
Ensure __va is given a physical address below PAGE_OFFSET, and __pa is
given a virtual address above PAGE_OFFSET.
It has check the PAGE_OFFSET in __pa, will test it and resend the
patch(with above warning changes).
What did you get with this commit? Is this what causes the crash?
I mean that your patch does the check to make sure the virt addr should
above PAGE_OFFSET,
and we can add the check in the virt_addr_valid too.
riscv for example with flatmem also relies on pfn_valid to do the right
thing, so as far as I can see the check should exclude vmalloc addresses
and it's just a matter of virt_addr_valid not to give virt_to_pfn an
address < PAGE_OFFSET.
If we take riscv's implementation
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 254687258f42..7713188516a6 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -132,7 +132,10 @@ static inline bool pfn_valid(unsigned long pfn)
#define virt_to_page(kaddr) pfn_to_page(virt_to_pfn(kaddr))
#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
-#define virt_addr_valid(kaddr) pfn_valid(virt_to_pfn(kaddr))
+#define virt_addr_valid(vaddr) ({ \
+ unsigned long _addr = (unsigned long)vaddr; \
+ (unsigned long)(_addr) >= PAGE_OFFSET && pfn_valid(virt_to_pfn(_addr)); \
+})
Yes, I send a new v2 with this change, thanks
/*
* On Book-E parts we need __va to parse the device tree and we can't
.
