On 9/17/21 4:21 AM, Geert Uytterhoeven wrote: > Hi Rob, > > On Fri, Sep 17, 2021 at 3:12 AM Rob Landley <rob@xxxxxxxxxxx> wrote: >> On 9/15/21 8:50 AM, Geert Uytterhoeven wrote: >> > arch/sh/include/asm/pgtable-3level.h:37:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] >> ... >> > The truncation to "unsigned long" has been there since forever, so >> > probably it still works fine ;-) >> >> 1) Linux is LP64 so sizeof(long) and sizeof(pointer) always match, so it's not >> truncating. >> >> 2) The sh5 only ever shipped evaluation units, it never had a production run, >> and we haven't implemented j64 yet, so all superh targets are currently 32 bit. >> (I.E. it's complaining about _expanding_ the pointer, which shouldn't be a >> problem as long as endianness is respected.) > > The build error is for 32-bit. I know. I'm just saying your fix doesn't seem wrong. (Personally I would have just cast once to (void *) and let C not being C++ do the right thing, but eh...) Not sure I understand the point of the original code though. Under what conditions do you want 64 bit page tables on a 32 bit system? (Some PAE variant?) > If CONFIG_X2TLB=y, pgd_t.pgd is "unsigned long long", i.e. 64-bit, so > casting it to a pointer needs an intermediate cast to "unsigned long". > See arch/sh/include/asm/page.h: I can't find a user of it. None of the existing defconfigs select this option: $ grep -r X2TLB arch/sh/configs And it's weird in other ways, like 8k page size. (Why...?) Google finds sh-x2 mentioned in Renesas' sh4a debugger docs, but I've never played with the renesas "a" variants. The stuff I'm familiar with is all following up on what Hitachi did, not Renesas. *shrug* You fix looks good enough to me. Acked-by: Rob Landley <rob@xxxxxxxxxxx> Rob
