Hello Sascha,
please drop this patch from all your stable-series queues....
It shouldn't be backported.
Thanks,
Helge
On 5/10/22 17:43, Sasha Levin wrote:
> From: Helge Deller <deller@xxxxxx>
>
> [ Upstream commit 6c800d7f55fcd78e17deae5ae4374d8e73482c13 ]
>
> This reverts commit a9fe7fa7d874a536e0540469f314772c054a0323.
>
> Leads to segfaults on 32bit kernel.
>
> Signed-off-by: Helge Deller <deller@xxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> arch/parisc/kernel/patch.c | 25 ++++++++++++++-----------
> 1 file changed, 14 insertions(+), 11 deletions(-)
>
> diff --git a/arch/parisc/kernel/patch.c b/arch/parisc/kernel/patch.c
> index e59574f65e64..80a0ab372802 100644
> --- a/arch/parisc/kernel/patch.c
> +++ b/arch/parisc/kernel/patch.c
> @@ -40,7 +40,10 @@ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags,
>
> *need_unmap = 1;
> set_fixmap(fixmap, page_to_phys(page));
> - raw_spin_lock_irqsave(&patch_lock, *flags);
> + if (flags)
> + raw_spin_lock_irqsave(&patch_lock, *flags);
> + else
> + __acquire(&patch_lock);
>
> return (void *) (__fix_to_virt(fixmap) + (uintaddr & ~PAGE_MASK));
> }
> @@ -49,7 +52,10 @@ static void __kprobes patch_unmap(int fixmap, unsigned long *flags)
> {
> clear_fixmap(fixmap);
>
> - raw_spin_unlock_irqrestore(&patch_lock, *flags);
> + if (flags)
> + raw_spin_unlock_irqrestore(&patch_lock, *flags);
> + else
> + __release(&patch_lock);
> }
>
> void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len)
> @@ -61,9 +67,8 @@ void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len)
> int mapped;
>
> /* Make sure we don't have any aliases in cache */
> - flush_kernel_dcache_range_asm(start, end);
> - flush_kernel_icache_range_asm(start, end);
> - flush_tlb_kernel_range(start, end);
> + flush_kernel_vmap_range(addr, len);
> + flush_icache_range(start, end);
>
> p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &flags, &mapped);
>
> @@ -76,10 +81,8 @@ void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len)
> * We're crossing a page boundary, so
> * need to remap
> */
> - flush_kernel_dcache_range_asm((unsigned long)fixmap,
> - (unsigned long)p);
> - flush_tlb_kernel_range((unsigned long)fixmap,
> - (unsigned long)p);
> + flush_kernel_vmap_range((void *)fixmap,
> + (p-fixmap) * sizeof(*p));
> if (mapped)
> patch_unmap(FIX_TEXT_POKE0, &flags);
> p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &flags,
> @@ -87,10 +90,10 @@ void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len)
> }
> }
>
> - flush_kernel_dcache_range_asm((unsigned long)fixmap, (unsigned long)p);
> - flush_tlb_kernel_range((unsigned long)fixmap, (unsigned long)p);
> + flush_kernel_vmap_range((void *)fixmap, (p-fixmap) * sizeof(*p));
> if (mapped)
> patch_unmap(FIX_TEXT_POKE0, &flags);
> + flush_icache_range(start, end);
> }
>
> void __kprobes __patch_text(void *addr, u32 insn)
