On Thu, 22 Oct 2020 at 17:57, Dmitry Osipenko <dig...@gmail.com> wrote: > > 22.10.2020 10:06, Ard Biesheuvel пишет: > > On Thu, 22 Oct 2020 at 05:30, Kees Cook <keesc...@chromium.org> wrote: > >> > >> On Thu, Oct 22, 2020 at 03:00:06AM +0300, Dmitry Osipenko wrote: > >>> 22.10.2020 02:40, Kees Cook пишет: > >>>> On Thu, Oct 22, 2020 at 01:57:37AM +0300, Dmitry Osipenko wrote: > >>>>> The vfp_kmode_exception() function now is unreachable using relative > >>>>> branching in THUMB2 kernel configuration, resulting in a "relocation > >>>>> truncated to fit: R_ARM_THM_JUMP19 against symbol `vfp_kmode_exception'" > >>>>> linker error. Let's use long jump in order to fix the issue. > >>>> > >>>> Eek. Is this with gcc or clang? > >>> > >>> GCC 9.3.0 > >>> > >>>>> Fixes: eff8728fe698 ("vmlinux.lds.h: Add PGO and AutoFDO input > >>>>> sections") > >>>> > >>>> Are you sure it wasn't 512dd2eebe55 ("arm/build: Add missing sections") ? > >>>> That commit may have implicitly moved the location of .vfp11_veneer, > >>>> though I thought I had chosen the correct position. > >>> > >>> I re-checked that the fixes tag is correct. > >>> > >>>>> Signed-off-by: Dmitry Osipenko <dig...@gmail.com> > >>>>> --- > >>>>> arch/arm/vfp/vfphw.S | 3 ++- > >>>>> 1 file changed, 2 insertions(+), 1 deletion(-) > >>>>> > >>>>> diff --git a/arch/arm/vfp/vfphw.S b/arch/arm/vfp/vfphw.S > >>>>> index 4fcff9f59947..6e2b29f0c48d 100644 > >>>>> --- a/arch/arm/vfp/vfphw.S > >>>>> +++ b/arch/arm/vfp/vfphw.S > >>>>> @@ -82,7 +82,8 @@ ENTRY(vfp_support_entry) > >>>>> ldr r3, [sp, #S_PSR] @ Neither lazy restore nor FP > >>>>> exceptions > >>>>> and r3, r3, #MODE_MASK @ are supported in kernel mode > >>>>> teq r3, #USR_MODE > >>>>> - bne vfp_kmode_exception @ Returns through lr > >>>>> + ldr r1, =vfp_kmode_exception > >>>>> + bxne r1 @ Returns through lr > >>>>> > >>>>> VFPFMRX r1, FPEXC @ Is the VFP enabled? > >>>>> DBGSTR1 "fpexc %08x", r1 > >>>> > >>>> This seems like a workaround though? I suspect the vfp11_veneer needs > >>>> moving? > >>>> > >>> > >>> I don't know where it needs to be moved. Please feel free to make a > >>> patch if you have a better idea, I'll be glad to test it. > >> > >> I might have just been distracted by the common "vfp" prefix. It's > >> possible that the text section shuffling just ended up being very large, > >> so probably this patch is right then! > >> > > > > I already sent a fix for this issue: > > > > https://www.armlinux.org.uk/developer/patches/viewpatch.php?id=9018/1 > > > > The offending commit contains stable tag, so I assume that fixes tag is > mandatory. Yours patch misses the fixes tag.
Russell, mind adding that? Or would you like me to update the patch in the patch system?