On Tue, Apr 1, 2014 at 3:54 PM, Laura Abbott <lau...@codeaurora.org> wrote: > On 4/1/2014 3:34 PM, Kees Cook wrote: >> On Mon, Mar 24, 2014 at 3:47 AM, Jon Medhurst (Tixy) <t...@linaro.org> wrote: >>> On Sun, 2014-03-23 at 16:21 -0600, Kees Cook wrote: >>>> For this stage, how about I make this "depends on KEXEC=n && >>>> KPROBES=n"? >>> >>> There's also ftrace (CONFIG_DYNAMIC_FTRACE I believe) which modifies >>> kernel code with a call to probe_kernel_write(), which GDB uses as well. >>> >>> And grepping for the patch_text() function also shows >>> __arch_jump_label_transform() modifies kernel code. Not sure how and >>> when that gets used. >> >> Right, so, I'm trying to fix ftrace now, and I've hit a wall. It is as >> if changes to the kernel text PMD aren't being noticed after the >> kernel is running. Does anyone know why this might be happening? >> >> Code and details here: >> https://lkml.org/lkml/2014/4/1/674 >> >> -Kees >> > > We had a flush_tlb_kernel_page after the pmd_flush in our out of tree code > which makes the text writeable in __patch_text.
I tried flush_tlb_kernel_range(), which I'd expect to do the same thing. I can try with _page() too. -Kees -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
