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 EF0B347607B; Fri, 7 Aug 2026 15:43:12 +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=1786117394; cv=none; b=SEcPUWYehryYX65AzYH4/x3aSIb/7GpAHh/SxB/ctiIEGD9OK1csn8W5oSOI0YsHbZWGjXtmY9BjD28KYM2GK5/D5VZ9m5nRVCUuGcfQ2ryfSFwKR65UtSXZnxjWE0LgU7D14NX1jITLvb0z6c9gnwz3OLzW1lKaa5RHFH5jXwE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786117394; c=relaxed/simple; bh=Nb2L0LE4/dsmlLHaZa4k6Pw6KesGdRgycoyFOwKTqhE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OnyUKFGwLnrg2gZhS1ZnbHUFiCMNzUd/LlUzzuuvhdN28PR1xn7/8ZLMF9RpxY/5/ICNSgbrj7fptqxr1kUQN2aWjPW74nU60vvB08myz8xqx9cDlzhpk3FQnSaUc1SOSSc6PwCTN83dyDkmQ4KWJ/+vdSuHGhjZgsycfEroGgY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FOLq0xmv; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FOLq0xmv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51B7D1F000E9; Fri, 7 Aug 2026 15:43:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786117392; bh=v7/FYfdfMrH+Kd4Ohs0PVwbPiHzQBMi1qYzeJ1o1H3k=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=FOLq0xmvwfmHAMvetXCG3j6/5eYjY+gicj9jeLp5bDAr4piad5ltbNti1V64abghC u+5UONXoC6glKS6x6yXAv3KTDq+bjpwkkCT9tj8XttsewByI0DLSQBpD+Fyw6ALKdU KSmgl6APAbmhtyHJr2bOHRBn73EEtxAlqSptxot8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiakai Xu , "Kiryl Shutsemau (Meta)" , Albert Ou , Alexandre Ghiti , David Hildenbrand , Guo Ren , Mike Rapoport , Muchun Song , Nam Cao , Palmer Dabbelt , "Vishal Moola (Oracle)" , Andrew Morton Subject: [PATCH 7.1 301/438] riscv/mm: use physical alignment for vmemmap_start_pfn Date: Fri, 7 Aug 2026 16:38:17 +0200 Message-ID: <20260807143434.389818187@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143428.008222056@linuxfoundation.org> References: <20260807143428.008222056@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiakai Xu commit 45ebe4540817cb540a59e4dc04014ac5dddc9990 upstream. RISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to VMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the physical-address domain. Commit 476849b0fba4 ("riscv/mm: align vmemmap to maximal folio size") attempted to account for the maximal folio alignment by feeding MAX_FOLIO_VMEMMAP_ALIGN directly into VMEMMAP_ADDR_ALIGN. However, MAX_FOLIO_VMEMMAP_ALIGN is measured in bytes of struct page storage, whereas VMEMMAP_ADDR_ALIGN is used to align a physical address. The mask-based compound_info encoding requires pfn_to_page(0) to be naturally aligned to MAX_FOLIO_VMEMMAP_ALIGN. Commit 9f94db4c7eaa ("mm/sparse: check memmap alignment for compound_info_has_mask()") added a check for that requirement and exposed the unit mismatch on systems such as QEMU virt, where the DRAM base is not aligned to MAX_FOLIO_NR_PAGES * PAGE_SIZE. Here is the log: [ 0.000000][ C0] ------------[ cut here ]------------ [ 0.000000][ C0] WARNING: mm/sparse.c:365 at sparse_init+0x58a/0x6fe, CPU#0: swapper/0 [ 0.000000][ C0] Modules linked in: [ 0.000000][ C0] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.2.0-rc3-g1d8304bdd65f #2 PREEMPT [ 0.000000][ C0] Hardware name: riscv-virtio,qemu (DT) [ 0.000000][ C0] epc : sparse_init+0x58a/0x6fe [ 0.000000][ C0] ra : sparse_init+0x58a/0x6fe [ 0.000000][ C0] epc : ffffffff86851c88 ra : ffffffff86851c88 sp : ffffffff88807a30 [ 0.000000][ C0] gp : ffffffff8a3bf240 tp : ffffffff88842080 t0 : ff600000ffab6000 [ 0.000000][ C0] t1 : 000000017fab6000 t2 : 65203a6573726363 s0 : ffffffff88807bc0 [ 0.000000][ C0] s1 : 000000000e000000 a0 : 0000000000000007 a1 : 0000000000000000 [ 0.000000][ C0] a2 : 0000000000000002 a3 : ffffffff86851c88 a4 : 0000000000000000 [ 0.000000][ C0] a5 : ffffffff88843080 a6 : 0000000000000003 a7 : 0000000000000000 [ 0.000000][ C0] s2 : ff60000000000000 s3 : 0040000000000000 s4 : 0004000000000000 [ 0.000000][ C0] s5 : ffffffff8a4d92e0 s6 : ff600000ffab55e0 s7 : ffffffff88384d00 [ 0.000000][ C0] s8 : 0000000000000003 s9 : ffffffff88384cc1 s10: ffffffff88384cc0 [ 0.000000][ C0] s11: ffffffff8a4daae0 t3 : ffffffff915e8b20 t4 : ffffffff915e8b20 [ 0.000000][ C0] t5 : ffffffff915e8b20 t6 : ffffffff915e8bc8 ssp : 0000000000000000 [ 0.000000][ C0] status: 0000000200000100 badaddr: ffffffff86851c88 cause: 0000000000000003 [ 0.000000][ C0] [] sparse_init+0x58a/0x6fe [ 0.000000][ C0] [] mm_core_init_early+0x116/0x1e30 [ 0.000000][ C0] [] start_kernel+0xd2/0x848 Convert MAX_FOLIO_VMEMMAP_ALIGN to the equivalent physical alignment before using it in VMEMMAP_ADDR_ALIGN. This keeps the existing round_down() logic while making the resulting vmemmap base satisfy the mask-alignment requirement. Link: https://lore.kernel.org/20260716115326.3466926-1-xujiakai2025@iscas.ac.cn Fixes: 476849b0fba4 ("riscv/mm: align vmemmap to maximal folio size") Signed-off-by: Jiakai Xu Reviewed-by: Kiryl Shutsemau (Meta) Cc: Albert Ou Cc: Alexandre Ghiti Cc: David Hildenbrand Cc: Guo Ren Cc: Mike Rapoport Cc: Muchun Song Cc: Nam Cao Cc: Palmer Dabbelt Cc: Vishal Moola (Oracle) Assisted-by: YuanSheng:DeepSeek-V4-Flash Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- arch/riscv/mm/init.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -61,7 +61,8 @@ EXPORT_SYMBOL(phys_ram_base); #ifdef CONFIG_SPARSEMEM_VMEMMAP #define VMEMMAP_ADDR_ALIGN max(1ULL << SECTION_SIZE_BITS, \ - MAX_FOLIO_VMEMMAP_ALIGN) + PFN_PHYS(MAX_FOLIO_VMEMMAP_ALIGN / \ + sizeof(struct page))) unsigned long vmemmap_start_pfn __ro_after_init; EXPORT_SYMBOL(vmemmap_start_pfn);