From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 25F29D2ECE9 for ; Tue, 20 Jan 2026 13:04:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6HK2XDqvr0szkHQ7whJ4JBYHd5Ew9QIOfMDRmAhXuEc=; b=0Jl97qZM9dZIqz3C2AH/QLtkjL yPPCbgYaAxsG1GyfTyLu0ciDY9cab1gFpCzhLHKXMM5pDKN7Azl6wztg8gcNXLPUIycj0142qCslw DfESQ9zLiNm7HoYmBfzshfwPy3GBssa9cp8be1yWZvWkWNMyAIHZ1MNNcaxmsGAuyVro2TIGE7Eal 3gWS4rqErKZovkvGXF1KZfB9C5un8o485h8EXOPr/1Z0WnpICKWmhCk3YTIwsS5y8HiphgvYviuKj PjKlrvgt74NNQQ6zLKw1D49b2MgfWb4g4b5DhgQNeMB4godl+Lk0h8I2WYWHkxwztnOpk7jSimBzB +6bbsy4Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1viBOm-00000003t0Z-3OhD; Tue, 20 Jan 2026 13:03:56 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1viBOl-00000003t0N-30zX for kexec@lists.infradead.org; Tue, 20 Jan 2026 13:03:55 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id D49AE60018; Tue, 20 Jan 2026 13:03:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E8C6FC16AAE; Tue, 20 Jan 2026 13:03:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768914234; bh=VjNsk+rGW49szc0ZaDC/PxUEhkP0A5D50M/kBU1Njlc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IjSYQTxZO9zOdD8dgFokigXt6el1iimLLAw18aUnWCJHji5YWJKX+76HBlEkC0+nm shaw36qPYg7q8aymOeUc3lZgVkWU+ZuL3raurQsht2qGETyMlHKnqwl1f/1l2xOSE7 iiEEMdG7DRfOK6PIa5SEklmz+dMki95fKZ3WxKkzgQ9ShoxwBZ4bDZveME7VZL4SoY OgiNyNxxlSRXkBaBmCB5/xXtUVHl/OrU5jFCwY1TWAblP/9hShU2Xm5skNyRpr0Aa9 6aK5NAYPw03LVj7OBXyWXzxMYZ1YG7auxZS7kGxuTX3RoBC9pZ7UpoE/YXaPqlD1pQ aEr2k0DRRsGLg== Date: Tue, 20 Jan 2026 15:03:48 +0200 From: Mike Rapoport To: Pratyush Yadav Cc: Andrew Morton , Alexander Graf , Pasha Tatashin , kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Suren Baghdasaryan Subject: Re: [PATCH v2 1/2] kho: use unsigned long for nr_pages Message-ID: References: <20260116112217.915803-1-pratyush@kernel.org> <20260116112217.915803-2-pratyush@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260116112217.915803-2-pratyush@kernel.org> X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Fri, Jan 16, 2026 at 11:22:14AM +0000, Pratyush Yadav wrote: > With 4k pages, a 32-bit nr_pages can span up to 16 TiB. While it is a > lot, there exist systems with terabytes of RAM. gup is also moving to > using long for nr_pages. Use unsigned long and make KHO future-proof. > > Suggested-by: Pasha Tatashin > Signed-off-by: Pratyush Yadav Reviewed-by: Mike Rapoport (Microsoft) > --- > > Changes in v2: > - New in v2. > > include/linux/kexec_handover.h | 6 +++--- > kernel/liveupdate/kexec_handover.c | 11 ++++++----- > 2 files changed, 9 insertions(+), 8 deletions(-) > > diff --git a/include/linux/kexec_handover.h b/include/linux/kexec_handover.h > index 5f7b9de97e8d..81814aa92370 100644 > --- a/include/linux/kexec_handover.h > +++ b/include/linux/kexec_handover.h > @@ -45,15 +45,15 @@ bool is_kho_boot(void); > > int kho_preserve_folio(struct folio *folio); > void kho_unpreserve_folio(struct folio *folio); > -int kho_preserve_pages(struct page *page, unsigned int nr_pages); > -void kho_unpreserve_pages(struct page *page, unsigned int nr_pages); > +int kho_preserve_pages(struct page *page, unsigned long nr_pages); > +void kho_unpreserve_pages(struct page *page, unsigned long nr_pages); > int kho_preserve_vmalloc(void *ptr, struct kho_vmalloc *preservation); > void kho_unpreserve_vmalloc(struct kho_vmalloc *preservation); > void *kho_alloc_preserve(size_t size); > void kho_unpreserve_free(void *mem); > void kho_restore_free(void *mem); > struct folio *kho_restore_folio(phys_addr_t phys); > -struct page *kho_restore_pages(phys_addr_t phys, unsigned int nr_pages); > +struct page *kho_restore_pages(phys_addr_t phys, unsigned long nr_pages); > void *kho_restore_vmalloc(const struct kho_vmalloc *preservation); > int kho_add_subtree(const char *name, void *fdt); > void kho_remove_subtree(void *fdt); > diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c > index 9dc51fab604f..709484fbf9fd 100644 > --- a/kernel/liveupdate/kexec_handover.c > +++ b/kernel/liveupdate/kexec_handover.c > @@ -222,7 +222,8 @@ static int __kho_preserve_order(struct kho_mem_track *track, unsigned long pfn, > static struct page *kho_restore_page(phys_addr_t phys, bool is_folio) > { > struct page *page = pfn_to_online_page(PHYS_PFN(phys)); > - unsigned int nr_pages, ref_cnt; > + unsigned long nr_pages; > + unsigned int ref_cnt; > union kho_page_info info; > > if (!page) > @@ -249,7 +250,7 @@ static struct page *kho_restore_page(phys_addr_t phys, bool is_folio) > * count of 1 > */ > ref_cnt = is_folio ? 0 : 1; > - for (unsigned int i = 1; i < nr_pages; i++) > + for (unsigned long i = 1; i < nr_pages; i++) > set_page_count(page + i, ref_cnt); > > if (is_folio && info.order) > @@ -283,7 +284,7 @@ EXPORT_SYMBOL_GPL(kho_restore_folio); > * > * Return: 0 on success, error code on failure > */ > -struct page *kho_restore_pages(phys_addr_t phys, unsigned int nr_pages) > +struct page *kho_restore_pages(phys_addr_t phys, unsigned long nr_pages) > { > const unsigned long start_pfn = PHYS_PFN(phys); > const unsigned long end_pfn = start_pfn + nr_pages; > @@ -829,7 +830,7 @@ EXPORT_SYMBOL_GPL(kho_unpreserve_folio); > * > * Return: 0 on success, error code on failure > */ > -int kho_preserve_pages(struct page *page, unsigned int nr_pages) > +int kho_preserve_pages(struct page *page, unsigned long nr_pages) > { > struct kho_mem_track *track = &kho_out.track; > const unsigned long start_pfn = page_to_pfn(page); > @@ -873,7 +874,7 @@ EXPORT_SYMBOL_GPL(kho_preserve_pages); > * kho_preserve_pages() call. Unpreserving arbitrary sub-ranges of larger > * preserved blocks is not supported. > */ > -void kho_unpreserve_pages(struct page *page, unsigned int nr_pages) > +void kho_unpreserve_pages(struct page *page, unsigned long nr_pages) > { > struct kho_mem_track *track = &kho_out.track; > const unsigned long start_pfn = page_to_pfn(page); > -- > 2.52.0.457.g6b5491de43-goog > -- Sincerely yours, Mike.