Below you find my version of the ptov function. I have just added a few lines 
and placed them under "#if defined(ARM)". The test is reasonable for ARM so I 
would appreciate if you include it. For other platforms please do whatever you 
like.

Jan


void
cmd_ptov(void)
{
        int c;
        ulong vaddr;
        physaddr_t paddr;
#if defined(ARM)
        physaddr_t paddr_tst;
#endif
        char buf1[BUFSIZE];
        char buf2[BUFSIZE];
        int others;

        while ((c = getopt(argcnt, args, "")) != EOF) {
                switch(c)
                {
                default:
                        argerrs++;
                        break;
                }
        }

        if (argerrs || !args[optind])
                cmd_usage(pc->curcmd, SYNOPSIS);

        others = 0;
        while (args[optind]) {
                paddr = htoll(args[optind], FAULT_ON_ERROR, NULL);
                vaddr = PTOV(paddr);

#if defined(ARM)
                if (kvtop(0, vaddr, &paddr_tst, 0) && paddr_tst==paddr) {
#endif
                fprintf(fp, "%s%s  %s\n", others++ ? "\n" : "", 
                    mkstring(buf1, VADDR_PRLEN, LJUST, "VIRTUAL"),
                    mkstring(buf2, VADDR_PRLEN, LJUST, "PHYSICAL"));
                fprintf(fp, "%s  %s\n",
                    mkstring(buf1, VADDR_PRLEN, LJUST|LONG_HEX, MKSTR(vaddr)),
                    mkstring(buf2, VADDR_PRLEN, LJUST|LONGLONG_HEX, 
                        MKSTR(&paddr)));
#if defined(ARM)
                } else {
                        fprintf(fp, "Unknown virtual address for physical 
address 0x%08llx\n", paddr);
                }
#endif

                optind++;
        }
}


Jan Karlsson
Senior Software Engineer
MIB
 
Sony Mobile Communications
Tel: +46703062174
sonymobile.com
 


-----Original Message-----
From: [email protected] 
[mailto:[email protected]] On Behalf Of Dave Anderson
Sent: torsdag den 5 juli 2012 15:48
To: Discussion list for crash utility usage, maintenance and development
Subject: Re: [Crash-utility] ptov command



----- Original Message -----
> 
> Hi Dave
> 
> I have a question about the ptov command. Ptov only handles kernel
> virtual addresses and their corresponding physical addresses.
> However if you give ptov a physical address that does not correspond
> to a kernel virtual address it still answers with an address. Users
> might get confused and do not know when to trust ptov, especially as
> the inverse command vtop always works.
> 
> So I would like to restrict ptov to give a result only when it is
> valid. The idea I have is that if ptov returns a valid virtual
> address then vtop on that address should give the same physical
> address back again. True??
> 
> cmd_ptov() in memory.c
> 
> ....
> 
> vaddr = PTOV(paddr);
> kvtop(0, vaddr, &paddr_tst, 0);
> if (paddr != paddr_tst) ... invalid vaddr, do not print it ...
> 
> Any comments?
> 
> Jan

Sounds reasonable, at least for the 32-bit arches.  I don't think it's
necessary for any 64-bit arch.  And you'd also need to account for kvtop()
failing outright (and returning FALSE).

Dave

--
Crash-utility mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/crash-utility

--
Crash-utility mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/crash-utility

Reply via email to