Re: [PATCH] m68k: Enable memtest functionality

From: Mike Rapoport
Date: Fri Nov 12 2021 - 07:34:37 EST


On Fri, Nov 12, 2021 at 09:05:31AM +0100, Geert Uytterhoeven wrote:
> Hi Finn,
>
> On Fri, Nov 12, 2021 at 1:37 AM Finn Thain <fthain@xxxxxxxxxxxxxx> wrote:
> > Enable the memtest functionality and rearrange some code to prevent it
> > from clobbering the initrd.
> >
> > The CONFIG_BLK_DEV_INITRD symbol was conditional on !defined(CONFIG_SUN3).
> > For simplicity, remove that test on the basis that m68k_ramdisk.size == 0
> > on Sun 3.
> >
> > The SLIME source code at
> > http://sammy.net/sun3/ftp/pub/m68k/sun3/slime/slime-2.0.tar.gz
> > indicates that no BI_RAMDISK entry is ever passed to the kernel due
> > to #ifdef 0 around the relevant code.
> >
> > Cc: Mike Rapoport <rppt@xxxxxxxxxx>
> > Cc: Sam Creasey <sammy@xxxxxxxxx>
> > Cc: Jonathan Corbet <corbet@xxxxxxx>
> > Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxx>
>
> Thanks for your patch!
>
> > --- a/arch/m68k/Kconfig
> > +++ b/arch/m68k/Kconfig
> > @@ -9,6 +9,7 @@ config M68K
> > select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS
> > select ARCH_MIGHT_HAVE_PC_PARPORT if ISA
> > select ARCH_NO_PREEMPT if !COLDFIRE
> > + select ARCH_USE_MEMTEST
>
> if MMU_MOTOROLA?
>
> > select ARCH_WANT_IPC_PARSE_VERSION
> > select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
> > select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE
> > diff --git a/arch/m68k/kernel/setup_mm.c b/arch/m68k/kernel/setup_mm.c
> > index 4b51bfd38e5f..49e573b94326 100644
> > --- a/arch/m68k/kernel/setup_mm.c
> > +++ b/arch/m68k/kernel/setup_mm.c
> > @@ -338,13 +338,6 @@ void __init setup_arch(char **cmdline_p)
> > panic("No configuration setup");
> > }
> >
> > - paging_init();
> > -
> > -#ifdef CONFIG_NATFEAT
> > - nf_init();
> > -#endif
> > -
> > -#ifndef CONFIG_SUN3
> > #ifdef CONFIG_BLK_DEV_INITRD
> > if (m68k_ramdisk.size) {
> > memblock_reserve(m68k_ramdisk.addr, m68k_ramdisk.size);
>
> Does this still work, given the initrd is part of memory that used
> to be added before (in paging_init(), but now is added later?
> (I'm no memblock expert, so that might be a silly question ;-)

memblock allows reserving non-existing memory just fine.

> > @@ -354,6 +347,12 @@ void __init setup_arch(char **cmdline_p)
> > }
> > #endif
> >
> > + paging_init();
> > +
> > +#ifdef CONFIG_NATFEAT
> > + nf_init();
> > +#endif
> > +
> > #ifdef CONFIG_ATARI
> > if (MACH_IS_ATARI)
> > atari_stram_reserve_pages((void *)availmem);
> > @@ -364,8 +363,6 @@ void __init setup_arch(char **cmdline_p)
> > }
> > #endif
> >
> > -#endif /* !CONFIG_SUN3 */
> > -
> > /* set ISA defs early as possible */
> > #if defined(CONFIG_ISA) && defined(MULTI_ISA)
> > if (MACH_IS_Q40) {
> > diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
> > index 9f3f77785aa7..5b6575eb6d02 100644
> > --- a/arch/m68k/mm/motorola.c
> > +++ b/arch/m68k/mm/motorola.c
> > @@ -455,6 +455,8 @@ void __init paging_init(void)
> >
> > flush_tlb_all();
> >
> > + early_memtest(min_addr, max_addr);
>
> So this is available only if MMU_MOTOROLA, not for Sun-3, Coldfire,
> or nommu.
>
> > +
> > /*
> > * initialize the bad page table and bad page to point
> > * to a couple of allocated pages
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds

--
Sincerely yours,
Mike.