From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CCBEB3DB32F; Mon, 8 Jun 2026 15:38:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780933112; cv=none; b=b3DHR5opC+s7QbOJvymzsP2+VGPjZw0+ZZP04tZdGC+ypHmZsMm87b/8UyPwRjIMxzFlv3pf7pe37Od+/8UEXMATiOEkvAqbq672IH3b5EnAXaYyUyiFLdm2JiKIbrbexpscYZHWOIWq01SX30X7P03LcJCYM0hjQv+QButq4kU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780933112; c=relaxed/simple; bh=XKi+0XzP0f1FDe3bf/9f9av1v2AA+IK6ZH+JJaORvUk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=o0hr261X1RwNiET35y+fiW0vatOCe6KNU6flDK+dZRGImJIzUVoV9Qpxe7LGRBDvkBVuS3KEUFlzGSrleAiEisQWFuzgwvdhR+kaPiAl55uvW7X8oZLLFJUzIXvHsid4W/kltb2FUrJGM3c0tiBG8MOE1QfANNYNdRkPI1/iflM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bQxyOqT/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bQxyOqT/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 503EB1F00893; Mon, 8 Jun 2026 15:38:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780933111; bh=i+8PnYD0gabW4Oe0rUJLesGb3GBzLwEDsBFUW101snk=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=bQxyOqT/AdkFJIeW2HC/zmb923F9BBOds3pOH3xHRMAOhodoJ6Nnhhru3TkjrN2dl VVIQzX/3Ausm/7OzU/HtweZ/x2+xUeysI3CwSHsCAwwzHxxEAL1LIb2/3uvgXfwIYd ZV/buSnjOWk3q43iF0Vn2mQg93Ew38J0RWKcBocDx7H1RhJ9yfnnjNe+TXPZgNZksW yrFZZpt7HO3X0exOPgiw7vpoBqLkNIXXwt86JAz4fkE/TfriTih+IDMBujPkwuhc2T HT24REevPf4eBpBeE1DmvJHbTMuY/facWnQtn6n7cnrOokvXBCFTk7YsJtecJVhVzC +5I0y1tM/OtTQ== Message-ID: Date: Mon, 8 Jun 2026 17:38:26 +0200 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 1/2] fs/proc/task_mmu: change lock_vma_range() to return error code To: Suren Baghdasaryan , akpm@linux-foundation.org Cc: liam@infradead.org, ljs@kernel.org, vbabka@kernel.org, willy@infradead.org, jannh@google.com, paulmck@kernel.org, pfalcato@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org References: <20260606015729.1837935-1-surenb@google.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/6/26 03:57, Suren Baghdasaryan wrote: > To correctly propagate error code from lock_vma_range(), change it to > return the error code instead of the boolean. This simplifies error > propagation code. > > Signed-off-by: Suren Baghdasaryan > --- > fs/proc/task_mmu.c | 16 +++++++++------- > 1 file changed, 9 insertions(+), 7 deletions(-) > > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > index d32408f7cd5e..023422fcee12 100644 > --- a/fs/proc/task_mmu.c > +++ b/fs/proc/task_mmu.c > @@ -162,13 +162,13 @@ static void unlock_ctx_vma(struct proc_maps_locking_ctx *lock_ctx) > } > } > > -static inline bool lock_vma_range(struct seq_file *m, > - struct proc_maps_locking_ctx *lock_ctx) > +static inline int lock_vma_range(struct seq_file *m, > + struct proc_maps_locking_ctx *lock_ctx) > { > rcu_read_lock(); > reset_lock_ctx(lock_ctx); > > - return true; > + return 0; > } > > static inline void unlock_vma_range(struct proc_maps_locking_ctx *lock_ctx) > @@ -245,10 +245,10 @@ static inline void unlock_ctx_mm(struct proc_maps_locking_ctx *lock_ctx) > mmap_read_unlock(lock_ctx->mm); > } > > -static inline bool lock_vma_range(struct seq_file *m, > +static inline int lock_vma_range(struct seq_file *m, > struct proc_maps_locking_ctx *lock_ctx) > { > - return lock_ctx_mm(lock_ctx) == 0; > + return lock_ctx_mm(lock_ctx); > } > > static inline void unlock_vma_range(struct proc_maps_locking_ctx *lock_ctx) > @@ -311,6 +311,7 @@ static void *m_start(struct seq_file *m, loff_t *ppos) > struct proc_maps_locking_ctx *lock_ctx; > loff_t last_addr = *ppos; > struct mm_struct *mm; > + int err; > > /* See m_next(). Zero at the start or after lseek. */ > if (last_addr == SENTINEL_VMA_END) > @@ -328,11 +329,12 @@ static void *m_start(struct seq_file *m, loff_t *ppos) > return NULL; > } > > - if (!lock_vma_range(m, lock_ctx)) { > + err = lock_vma_range(m, lock_ctx); > + if (err) { > mmput(mm); > put_task_struct(priv->task); > priv->task = NULL; > - return ERR_PTR(-EINTR); > + return ERR_PTR(err); Looks good: down_read_killable() would also have returned -EINTR. Acked-by: David Hildenbrand (Arm) -- Cheers, David