From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH] riscv: fixup max_low_pfn with PFN_DOWN. Date: Tue, 15 Jan 2019 07:36:13 -0800 Message-ID: <20190115153613.GC26443@infradead.org> References: <1547280987-7630-1-git-send-email-guoren@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1547280987-7630-1-git-send-email-guoren@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: guoren@kernel.org Cc: palmer@sifive.com, aou@eecs.berkeley.edu, linux-arch@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren , Mao Han List-Id: linux-arch.vger.kernel.org On Sat, Jan 12, 2019 at 04:16:27PM +0800, guoren@kernel.org wrote: > From: Guo Ren > > max_low_pfn should be pfn_size not byte_size. > > Signed-off-by: Guo Ren > Signed-off-by: Mao Han > Cc: Palmer Dabbelt > Cc: Albert Ou > --- > arch/riscv/kernel/setup.c | 2 +- > arch/riscv/mm/init.c | 3 ++- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > index fc8006a..5463e67 100644 > --- a/arch/riscv/kernel/setup.c > +++ b/arch/riscv/kernel/setup.c > @@ -174,7 +174,7 @@ static void __init setup_bootmem(void) > BUG_ON(mem_size == 0); > > set_max_mapnr(PFN_DOWN(mem_size)); > - max_low_pfn = memblock_end_of_DRAM(); > + max_low_pfn = PFN_DOWN(memblock_end_of_DRAM()); I know it is used just above, but can we please just switch this code to use >> PAGE_SHIFT instead of PFN_DOWN, which just horribly obsfucates what is going on? > > #ifdef CONFIG_BLK_DEV_INITRD > setup_initrd(); > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 1d9bfaf..658ebf6 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -28,7 +28,8 @@ static void __init zone_sizes_init(void) > unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; > > #ifdef CONFIG_ZONE_DMA32 > - max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn)); > + max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, > + (unsigned long) PFN_PHYS(max_low_pfn))); > #endif Same comment as above here, plus I think we should just use memblock_end_of_DRAM directly, e.g. something like: static const phys_addr_t max_dma32_addr = 4UL * SZ_1G; max_zone_pfns[ZONE_DMA32] = min(memblock_end_of_DRAM(), max_dma32_addr) >> PAGE_SHIFT; From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.133]:41248 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728652AbfAOPgP (ORCPT ); Tue, 15 Jan 2019 10:36:15 -0500 Date: Tue, 15 Jan 2019 07:36:13 -0800 From: Christoph Hellwig Subject: Re: [PATCH] riscv: fixup max_low_pfn with PFN_DOWN. Message-ID: <20190115153613.GC26443@infradead.org> References: <1547280987-7630-1-git-send-email-guoren@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1547280987-7630-1-git-send-email-guoren@kernel.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: guoren@kernel.org Cc: palmer@sifive.com, aou@eecs.berkeley.edu, linux-arch@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren , Mao Han Message-ID: <20190115153613._e-kj3KdQXKLaR3fp5VxpBuCRBPLGaGx-9xaDZe5cno@z> On Sat, Jan 12, 2019 at 04:16:27PM +0800, guoren@kernel.org wrote: > From: Guo Ren > > max_low_pfn should be pfn_size not byte_size. > > Signed-off-by: Guo Ren > Signed-off-by: Mao Han > Cc: Palmer Dabbelt > Cc: Albert Ou > --- > arch/riscv/kernel/setup.c | 2 +- > arch/riscv/mm/init.c | 3 ++- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c > index fc8006a..5463e67 100644 > --- a/arch/riscv/kernel/setup.c > +++ b/arch/riscv/kernel/setup.c > @@ -174,7 +174,7 @@ static void __init setup_bootmem(void) > BUG_ON(mem_size == 0); > > set_max_mapnr(PFN_DOWN(mem_size)); > - max_low_pfn = memblock_end_of_DRAM(); > + max_low_pfn = PFN_DOWN(memblock_end_of_DRAM()); I know it is used just above, but can we please just switch this code to use >> PAGE_SHIFT instead of PFN_DOWN, which just horribly obsfucates what is going on? > > #ifdef CONFIG_BLK_DEV_INITRD > setup_initrd(); > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 1d9bfaf..658ebf6 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -28,7 +28,8 @@ static void __init zone_sizes_init(void) > unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; > > #ifdef CONFIG_ZONE_DMA32 > - max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn)); > + max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, > + (unsigned long) PFN_PHYS(max_low_pfn))); > #endif Same comment as above here, plus I think we should just use memblock_end_of_DRAM directly, e.g. something like: static const phys_addr_t max_dma32_addr = 4UL * SZ_1G; max_zone_pfns[ZONE_DMA32] = min(memblock_end_of_DRAM(), max_dma32_addr) >> PAGE_SHIFT;