From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Date: Sat, 01 Aug 2020 10:18:54 +0000 Subject: Re: [PATCH 06/15] powerpc: fadamp: simplify fadump_reserve_crash_area() Message-Id: <20200801101854.GD534153@kernel.org> List-Id: References: <20200728051153.1590-1-rppt@kernel.org> <20200728051153.1590-7-rppt@kernel.org> <87d04d5hda.fsf@mpe.ellerman.id.au> In-Reply-To: <87d04d5hda.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michael Ellerman Cc: linux-sh@vger.kernel.org, Peter Zijlstra , Benjamin Herrenschmidt , Dave Hansen , Hari Bathini , linux-mips@vger.kernel.org, Max Filippov , Paul Mackerras , sparclinux@vger.kernel.org, linux-riscv@lists.infradead.org, Will Deacon , Stafford Horne , Marek Szyprowski , linux-s390@vger.kernel.org, linux-c6x-dev@linux-c6x.org, Yoshinori Sato , x86@kernel.org, Russell King , Mike Rapoport , clang-built-linux@googlegroups.com, Ingo Molnar , Catalin Marinas , uclinux-h8-devel@lists.sourceforge.jp, linux-xtensa@linux-xtensa.org, openrisc@lists.librecores.org, Borislav Petkov , Andy Lutomirski , Paul Walmsley , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Michal Simek , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Palmer Dabbelt , Andrew Morton , Christoph Hellwig On Thu, Jul 30, 2020 at 10:15:13PM +1000, Michael Ellerman wrote: > Mike Rapoport writes: > > From: Mike Rapoport > > > > fadump_reserve_crash_area() reserves memory from a specified base address > > till the end of the RAM. > > > > Replace iteration through the memblock.memory with a single call to > > memblock_reserve() with appropriate that will take care of proper memory > ^ > parameters? > > reservation. > > > > Signed-off-by: Mike Rapoport > > --- > > arch/powerpc/kernel/fadump.c | 20 +------------------- > > 1 file changed, 1 insertion(+), 19 deletions(-) > > I think this looks OK to me, but I don't have a setup to test it easily. > I've added Hari to Cc who might be able to. > > But I'll give you an ack in the hope that it works :) Actually, I did some digging in the git log and the traversal was added there on purpose by the commit b71a693d3db3 ("powerpc/fadump: exclude memory holes while reserving memory in second kernel") Presuming this is still reqruired I'm going to drop this patch and will simply replace for_each_memblock() with for_each_mem_range() in v2. > Acked-by: Michael Ellerman > > > > diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c > > index 78ab9a6ee6ac..2446a61e3c25 100644 > > --- a/arch/powerpc/kernel/fadump.c > > +++ b/arch/powerpc/kernel/fadump.c > > @@ -1658,25 +1658,7 @@ int __init fadump_reserve_mem(void) > > /* Preserve everything above the base address */ > > static void __init fadump_reserve_crash_area(u64 base) > > { > > - struct memblock_region *reg; > > - u64 mstart, msize; > > - > > - for_each_memblock(memory, reg) { > > - mstart = reg->base; > > - msize = reg->size; > > - > > - if ((mstart + msize) < base) > > - continue; > > - > > - if (mstart < base) { > > - msize -= (base - mstart); > > - mstart = base; > > - } > > - > > - pr_info("Reserving %lluMB of memory at %#016llx for preserving crash data", > > - (msize >> 20), mstart); > > - memblock_reserve(mstart, msize); > > - } > > + memblock_reserve(base, memblock_end_of_DRAM() - base); > > } > > > > unsigned long __init arch_reserved_kernel_pages(void) > > -- > > 2.26.2 -- Sincerely yours, Mike.