On Wed, Aug 24, 2016 at 02:37:21PM -0400, Linus Torvalds wrote: > On Wed, Aug 24, 2016 at 2:22 PM, Peter Zijlstra <pet...@infradead.org> wrote: > > > > I actively disable KASLR on my dev box and feed these hex numbers into > > addr2line -ie vmlinux to find where in the function we are. > > > > Having the option to make %pB generate them works for me. > > Yeah, considering that this is the only place this is used, changing > %pB sounds quite reasonable.
There's now another use of '%pB' in proc_pid_stack() in the tip tree: I changed it to '%pB' from '%pS'. But I think the modified '%pB' would work there as well. > We could perhaps make %pB show the hex numbers and address (so pB > would expand to "[<hex>] symbolname".if > > (a) not randomizing (so the hex numbers _may_ be useful) > > (b) kptr_restrict is 0 (so the hex numbers are "safe" in the dmesg) > > and fall back to just the symbolic name if either of those aren't true? Do we really need to check for both? '%pK' only checks kptr_restrict. I'd think we should be consistent with that. And maybe there are some scenarios where the actual text addresses provide useful debug information if KASLR is enabled and kptr_restrict is zero. > And obviously, if KALLSYMS isn't enabled, you always show hex > numbers.. That's already the case (but we might want to add the "[<>}' > markers around the hex numbers just to make the user space automation > we do have work). Even if kptr_restrict is set? -- Josh
