From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6E62F61FFE for ; Wed, 5 Nov 2025 05:30:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762320658; cv=none; b=oY8BkOBD8OvzXxpbW9UIv0iNdBmmngO17iwXJkg1RGT2W3K7QKZEBY6NIGDUcICNp1OLC9KoL/RhSqTgLY0L4Ot56W+YPeT0OLbJRxGO0GzzQGxIWgU4kMBiaHRPegJdppYgpgApbscvxGgXaHvVhRQJyI//mXhU7EzTKWq0jUA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762320658; c=relaxed/simple; bh=PRVgeTloQ/TAqQkbtjz5p3/sPSwlYj6HYwL71a7QobQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=chTIjmFX++Kf1whAaJCJZHnVZ/KlDG5mDEqf1isZyUglAHmuoLv2OUIfhhDU2Kh+ZUb0Twx3m6mpqSSDJ/y2p9mYumwOpfhefds9Xg4FdJVZOFa0Peoz/+9/IhVBM1zAH20rlssBBc32SWZR+rXZGVKap9jLcupZDwFexRpF/PM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AC9E616F2; Tue, 4 Nov 2025 21:30:46 -0800 (PST) Received: from [10.164.18.45] (unknown [10.164.18.45]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C9D8C3F63F; Tue, 4 Nov 2025 21:30:52 -0800 (PST) Message-ID: Date: Wed, 5 Nov 2025 11:00:49 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] arm64/mm: Drop redundant extern declaration for rodata_full To: Will Deacon Cc: linux-arm-kernel@lists.infradead.org, Catalin Marinas , linux-kernel@vger.kernel.org, ryan.roberts@arm.com References: <20251015023609.427911-1-anshuman.khandual@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 04/11/25 9:13 PM, Will Deacon wrote: > On Wed, Oct 15, 2025 at 03:36:09AM +0100, Anshuman Khandual wrote: >> Drop the redundant extern declaration 'rodata_full' which can be included >> via the header after moving exiting declaration outside the >> function arch_parse_debug_rodata(). While here also drop 'rodata_enabled' >> which is anyways available via the generic header . >> >> Cc: Catalin Marinas >> Cc: Will Deacon >> Cc: linux-arm-kernel@lists.infradead.org >> Cc: linux-kernel@vger.kernel.org >> Signed-off-by: Anshuman Khandual >> --- >> arch/arm64/include/asm/mmu_context.h | 2 -- >> arch/arm64/include/asm/setup.h | 4 +--- >> 2 files changed, 1 insertion(+), 5 deletions(-) >> >> diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h >> index 0375ca3162ff..e4b3563e1d96 100644 >> --- a/arch/arm64/include/asm/mmu_context.h >> +++ b/arch/arm64/include/asm/mmu_context.h >> @@ -26,8 +26,6 @@ >> #include >> #include >> >> -extern bool rodata_full; >> - >> static inline void contextidr_thread_switch(struct task_struct *next) >> { >> if (!IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR)) >> diff --git a/arch/arm64/include/asm/setup.h b/arch/arm64/include/asm/setup.h >> index 3d96dde4d214..902f1aab520f 100644 >> --- a/arch/arm64/include/asm/setup.h >> +++ b/arch/arm64/include/asm/setup.h >> @@ -12,12 +12,10 @@ >> */ >> extern phys_addr_t __fdt_pointer __initdata; >> extern u64 __cacheline_aligned boot_args[4]; >> +extern bool rodata_full; >> >> static inline bool arch_parse_debug_rodata(char *arg) >> { >> - extern bool rodata_enabled; >> - extern bool rodata_full; >> - >> if (!arg) >> return false; > > It would probably be cleaner to make 'rodata_full' static in mm/pageattr.c, > move the guts of arch_parse_debug_rodata in there and then consolidate > can_set_direct_map() and force_pte_mapping(). > > You need to talk to Ryan for the last part, as David's made some > suggestions around that too. Sure will talk to Ryan about this. But for the above suggestion - probably something like the following (untested) should work. diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index 0dbe3b29049b..ddb964e916e1 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -26,8 +26,6 @@ #include #include -extern bool rodata_full; - static inline void contextidr_thread_switch(struct task_struct *next) { if (!IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR)) diff --git a/arch/arm64/include/asm/setup.h b/arch/arm64/include/asm/setup.h index 3d96dde4d214..fa77a7208826 100644 --- a/arch/arm64/include/asm/setup.h +++ b/arch/arm64/include/asm/setup.h @@ -13,32 +13,7 @@ extern phys_addr_t __fdt_pointer __initdata; extern u64 __cacheline_aligned boot_args[4]; -static inline bool arch_parse_debug_rodata(char *arg) -{ - extern bool rodata_enabled; - extern bool rodata_full; - - if (!arg) - return false; - - if (!strcmp(arg, "on")) { - rodata_enabled = rodata_full = true; - return true; - } - - if (!strcmp(arg, "off")) { - rodata_enabled = rodata_full = false; - return true; - } - - if (!strcmp(arg, "noalias")) { - rodata_enabled = true; - rodata_full = false; - return true; - } - - return false; -} +bool arch_parse_debug_rodata(char *arg); #define arch_parse_debug_rodata arch_parse_debug_rodata #endif diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index b8d37eb037fc..030ee4ba8a7a 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1014,9 +1014,7 @@ static inline bool force_pte_mapping(void) bool bbml2 = system_capabilities_finalized() ? system_supports_bbml2_noabort() : cpu_supports_bbml2_noabort(); - return (!bbml2 && (rodata_full || arm64_kfence_can_set_direct_map() || - is_realm_world())) || - debug_pagealloc_enabled(); + return debug_pagealloc_enabled() || (!bbml2 && can_set_direct_map()); } static void __init map_mem(pgd_t *pgdp) diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 5135f2d66958..60d372c630eb 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -80,7 +80,31 @@ static const struct mm_walk_ops pageattr_ops = { .pte_entry = pageattr_pte_entry, }; -bool rodata_full __ro_after_init = true; +static bool rodata_full __ro_after_init = true; + +bool arch_parse_debug_rodata(char *arg) +{ + if (!arg) + return false; + + if (!strcmp(arg, "on")) { + rodata_enabled = rodata_full = true; + return true; + } + + if (!strcmp(arg, "off")) { + rodata_enabled = rodata_full = false; + return true; + } + + if (!strcmp(arg, "noalias")) { + rodata_enabled = true; + rodata_full = false; + return true; + } + + return false; +} bool can_set_direct_map(void) { -- 2.30.2