From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anshuman Khandual Date: Tue, 10 Mar 2020 13:58:42 +0000 Subject: Re: [PATCH V2] mm/special: Create generic fallbacks for pte_special() and pte_mkspecial() Message-Id: List-Id: References: <1583802551-15406-1-git-send-email-anshuman.khandual@arm.com> <20200310132747.GA12601@alpha.franken.de> In-Reply-To: <20200310132747.GA12601@alpha.franken.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Thomas Bogendoerfer Cc: linux-mm@kvack.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , Russell King , Guo Ren , Brian Cain , Tony Luck , Fenghua Yu , Geert Uytterhoeven , Sam Creasey , Michal Simek , Ralf Baechle , Paul Burton , Nick Hu , Greentime Hu , Vincent Chen , Ley Foon Tan , Jonas Bonn , Stefan Kristiansson , Stafford Horne , "James E.J. Bottomley" , Helge Deller , "David S. Miller" , Jeff Dike , Richard Weinberger , Anton Ivanov , Guan Xuetao , Chris Zankel , Max Filippov , Andrew Morton , linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, nios2-dev@lists.rocketboards.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org On 03/10/2020 06:57 PM, Thomas Bogendoerfer wrote: > On Tue, Mar 10, 2020 at 06:39:11AM +0530, Anshuman Khandual wrote: >> diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h >> index aef5378f909c..8e4e4be1ca00 100644 >> --- a/arch/mips/include/asm/pgtable.h >> +++ b/arch/mips/include/asm/pgtable.h >> @@ -269,6 +269,36 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, >> */ >> extern pgd_t swapper_pg_dir[]; >> >> +/* >> + * Platform specific pte_special() and pte_mkspecial() definitions >> + * are required only when ARCH_HAS_PTE_SPECIAL is enabled. >> + */ >> +#if !defined(CONFIG_32BIT) && !defined(CONFIG_CPU_HAS_RIXI) > > this looks wrong. > > current Kconfig statement is > > select ARCH_HAS_PTE_SPECIAL if !(32BIT && CPU_HAS_RIXI) > > so we can't use PTE_SPECIAL on 32bit _and_ CPUs with RIXI support. I already had asked for clarification on this. > > Why can't we use > > #if defined(CONFIG_ARCH_HAS_PTE_SPECIAL) > > here as the comment already suggests ? Yes, that will be easier and will automatically adjust in case ARCH_HAS_PTE_SPECIAL scope changes later. Will respin the patch. > > Thomas. >