On Wednesday, April 14, 2021 7:03:13 AM UTC you wrote: > Hi, > > Le 4/12/21 à 3:08 AM, Jisheng Zhang a écrit : > > Hi Jiuyang, > > > > On Mon, 12 Apr 2021 00:05:30 +0000 Jiuyang Liu <[email protected]> wrote: > >> This patch implements flush_cache_vmap for RISC-V, since it modifies PTE. > >> Without this patch, SFENCE.VMA won't be added to related codes, which > >> might introduce a bug in the out-of-order micro-architecture > >> implementations. > >> > >> Signed-off-by: Jiuyang Liu <[email protected]> > >> Reviewed-by: Alexandre Ghiti <[email protected]> > >> Reviewed-by: Palmer Dabbelt <[email protected]> > > > > IIRC, Palmer hasn't given this Reviewed-by tag. > > > >> --- > > > > Could you plz add version and changes? IIRC, this is the v3. > > > >> arch/riscv/include/asm/cacheflush.h | 6 ++++++ > >> 1 file changed, 6 insertions(+) > >> > >> diff --git a/arch/riscv/include/asm/cacheflush.h > >> b/arch/riscv/include/asm/cacheflush.h index 23ff70350992..3fd528badc35 > >> 100644 > >> --- a/arch/riscv/include/asm/cacheflush.h > >> +++ b/arch/riscv/include/asm/cacheflush.h > >> @@ -30,6 +30,12 @@ static inline void flush_dcache_page(struct page > >> *page) > >> > >> #define flush_icache_user_page(vma, pg, addr, len) \ > >> > >> flush_icache_mm(vma->vm_mm, 0) > >> > >> +/* > >> + * flush_cache_vmap is invoked after map_kernel_range() has installed > >> the page + * table entries, which modifies PTE, SFENCE.VMA should be > >> inserted.> > > Just my humble opinion, flush_cache_vmap() may not be necessary. > > vmalloc_fault can take care of this, and finally sfence.vma is inserted > > in related path. > I believe Palmer and Jisheng are right, my initial proposal to implement > flush_cache_vmap is wrong. > > But then, Jiuyang should not have noticed any problem here, so what's > wrong? @Jiuyang: Does implementing flush_cache_vmap fix your issue? Yes, I just checked this today, it did fix our issue. But I'm happy to rework on this, thanks for your help! This week I will try to trace wave of our core, and give a more detail email then. > And regarding flush_cache_vunmap, from Jisheng call stack, it seems also > not necessary. > > @Jiuyang: Can you tell us more about what you noticed? > > > Regards > > > >> + */ > >> +#define flush_cache_vmap(start, end) flush_tlb_all() > >> + > >> > >> #ifndef CONFIG_SMP > >> > >> #define flush_icache_all() local_flush_icache_all() > >> > >> -- > >> 2.31.1 > > > > _______________________________________________ > > linux-riscv mailing list > > [email protected] > > http://lists.infradead.org/mailman/listinfo/linux-riscv
Thanks, Jiuyang
