Re: [PATCH-for-8.0 v3] target/arm: Fix non-TCG build failure by inlining pauth_ptr_mask()

[Philippe Mathieu-Daudé]

On 30/3/23 12:34, Peter Maydell wrote:
> On Thu, 30 Mar 2023 at 11:31, Peter Maydell <peter.maydell@linaro.org> wrote:
> > On Tue, 28 Mar 2023 at 22:25, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
> > > aarch64_gdb_get_pauth_reg() -- although disabled since commit
> > > 5787d17a42 ("target/arm: Don't advertise aarch64-pauth.xml to
> > > gdb") is still compiled in. It calls pauth_ptr_mask() which is
> > > located in target/arm/tcg/pauth_helper.c, a TCG specific helper.
> > >
> > > To avoid a linking error when TCG is not enabled:
> > >
> > >    Undefined symbols for architecture arm64:
> > >      "_pauth_ptr_mask", referenced from:
> > >          _aarch64_gdb_get_pauth_reg in target_arm_gdbstub64.c.o
> > >    ld: symbol(s) not found for architecture arm64
> > >    clang: error: linker command failed with exit code 1 (use -v to see 
> > > invocation)
> > >
> > > - Inline pauth_ptr_mask() in aarch64_gdb_get_pauth_reg()
> > >    (this is the single user),
> > > - Rename pauth_ptr_mask_internal() as pauth_ptr_mask() and
> > >    inline it in "internals.h",
> > >
> > > Fixes: e995d5cce4 ("target/arm: Implement gdbstub pauth extension")
> > > Suggested-by: Richard Henderson <richard.henderson@linaro.org>
> > > Reviewed-by: Fabiano Rosas <farosas@suse.de>
> > > Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> > > ---
> > > Supersedes: <20230328133054.6553-1-philmd@linaro.org>
> > >
> > > Since v2:
> > > - Rebased (patch #1 merged)
> > > - Addressed rth's comments
> > > - Added R-b tags
> > > ---
> > >   target/arm/internals.h        | 16 +++++++---------
> > >   target/arm/gdbstub64.c        |  7 +++++--
> > >   target/arm/tcg/pauth_helper.c | 18 +-----------------
> > >   3 files changed, 13 insertions(+), 28 deletions(-)
> > >
> > > diff --git a/target/arm/internals.h b/target/arm/internals.h
> > > index 673519a24a..71f4c6d8a2 100644
> > > --- a/target/arm/internals.h
> > > +++ b/target/arm/internals.h
> > > @@ -1389,15 +1389,13 @@ int exception_target_el(CPUARMState *env);
> > >   bool arm_singlestep_active(CPUARMState *env);
> > >   bool arm_generate_debug_exceptions(CPUARMState *env);
> > >
> > > -/**
> > > - * pauth_ptr_mask:
> > > - * @env: cpu context
> > > - * @ptr: selects between TTBR0 and TTBR1
> > > - * @data: selects between TBI and TBID
> > > - *
> > > - * Return a mask of the bits of @ptr that contain the authentication code.
> > > - */
> > > -uint64_t pauth_ptr_mask(CPUARMState *env, uint64_t ptr, bool data);
> > > +static inline uint64_t pauth_ptr_mask(ARMVAParameters param)
> > > +{
> > > +    int bot_pac_bit = 64 - param.tsz;
> > > +    int top_pac_bit = 64 - 8 * param.tbi;
> > > +
> > > +    return MAKE_64BIT_MASK(bot_pac_bit, top_pac_bit - bot_pac_bit);
> > > +}
> >
> > Any reason for deleting the doc comment ?
>
> Applied to target-arm.next with a doc comment:
>
> /**
>   * pauth_ptr_mask:
>   * @param: parameters defining the MMU setup
>   *
>   * Return a mask of the address bits that contain the authentication code,
>   * given the MMU config defined by @param.
>   */

Thank you!