Re: [PATCH] RISC-V: Remove unused code from STRICT_KERNEL_RWX

[Palmer Dabbelt]

On Tue, 05 May 2020 17:00:05 PDT (-0700), atishp@xxxxxxxxxxxxxx wrote:
> On Tue, May 5, 2020 at 4:55 PM Palmer Dabbelt <palmer@xxxxxxxxxxx> wrote:
> > On Sun, 03 May 2020 21:03:19 PDT (-0700), Atish Patra wrote:
> > > This patch removes the unused functions set_kernel_text_rw/ro.
> > > Currently, it is not being invoked from anywhere and no other architecture
> > > (except arm) uses this code. Even in ARM, these functions are not invoked
> > > from anywhere currently.
> > >
> > > Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
> > >
> > > Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> > > ---
> > >  arch/riscv/mm/init.c | 16 ----------------
> > >  1 file changed, 16 deletions(-)
> > >
> > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> > > index b55be44ff9bd..ba60a581e9b6 100644
> > > --- a/arch/riscv/mm/init.c
> > > +++ b/arch/riscv/mm/init.c
> > > @@ -501,22 +501,6 @@ static inline void setup_vm_final(void)
> > >  #endif /* CONFIG_MMU */
> > >
> > >  #ifdef CONFIG_STRICT_KERNEL_RWX
> > > -void set_kernel_text_rw(void)
> > > -{
> > > -     unsigned long text_start = (unsigned long)_text;
> > > -     unsigned long text_end = (unsigned long)_etext;
> > > -
> > > -     set_memory_rw(text_start, (text_end - text_start) >> PAGE_SHIFT);
> > > -}
> > > -
> > > -void set_kernel_text_ro(void)
> > > -{
> > > -     unsigned long text_start = (unsigned long)_text;
> > > -     unsigned long text_end = (unsigned long)_etext;
> > > -
> > > -     set_memory_ro(text_start, (text_end - text_start) >> PAGE_SHIFT);
> > > -}
> > > -
> > >  void mark_rodata_ro(void)
> > >  {
> > >       unsigned long text_start = (unsigned long)_text;
> >
> > Thanks, this is on fixes.  Are you going to remove the ARM code as well?
>
> Yeah and also I realized that I forgot to remove the declarations from
> the header file.
> My bad. I will send out a v2. Please drop this one and take v2.

I just fixed it up

commit 73cb8e2a5863ccc5215660f5123db621bd57dff7
gpg: Signature made Tue 05 May 2020 05:02:17 PM PDT
gpg:                using RSA key 2B3C3747446843B24A943A7A2E1319F35FBB1889
gpg:                issuer "palmer@xxxxxxxxxxx"
gpg: Good signature from "Palmer Dabbelt <palmer@xxxxxxxxxxx>" [ultimate]
gpg:                 aka "Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>" [ultimate]
Author: Atish Patra <atish.patra@xxxxxxx>
Date:   Sun May 3 21:03:19 2020 -0700

   RISC-V: Remove unused code from STRICT_KERNEL_RWX
   
   This patch removes the unused functions set_kernel_text_rw/ro.
   Currently, it is not being invoked from anywhere and no other architecture
   (except arm) uses this code. Even in ARM, these functions are not invoked
   from anywhere currently.
   
   Fixes: d27c3c90817e ("riscv: add STRICT_KERNEL_RWX support")
   Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
   Reviewed-by: Zong Li <zong.li@xxxxxxxxxx>
   Signed-off-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>

diff --git a/arch/riscv/include/asm/set_memory.h b/arch/riscv/include/asm/set_memory.h
index c38df4771c09..4c5bae7ca01c 100644
--- a/arch/riscv/include/asm/set_memory.h
+++ b/arch/riscv/include/asm/set_memory.h
@@ -22,14 +22,6 @@ static inline int set_memory_x(unsigned long addr, int numpages) { return 0; }
static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; }
#endif

-#ifdef CONFIG_STRICT_KERNEL_RWX
-void set_kernel_text_ro(void);
-void set_kernel_text_rw(void);
-#else
-static inline void set_kernel_text_ro(void) { }
-static inline void set_kernel_text_rw(void) { }
-#endif
-
int set_direct_map_invalid_noflush(struct page *page);
int set_direct_map_default_noflush(struct page *page);

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 5b813532db59..27a334106708 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -502,22 +502,6 @@ static inline void setup_vm_final(void)
#endif /* CONFIG_MMU */

#ifdef CONFIG_STRICT_KERNEL_RWX
-void set_kernel_text_rw(void)
-{
-	unsigned long text_start = (unsigned long)_text;
-	unsigned long text_end = (unsigned long)_etext;
-
-	set_memory_rw(text_start, (text_end - text_start) >> PAGE_SHIFT);
-}
-
-void set_kernel_text_ro(void)
-{
-	unsigned long text_start = (unsigned long)_text;
-	unsigned long text_end = (unsigned long)_etext;
-
-	set_memory_ro(text_start, (text_end - text_start) >> PAGE_SHIFT);
-}
-
void mark_rodata_ro(void)
{
	unsigned long text_start = (unsigned long)_text;