From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752572AbdEQDjy (ORCPT ); Tue, 16 May 2017 23:39:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52082 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752303AbdEQDju (ORCPT ); Tue, 16 May 2017 23:39:50 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 20D79369C4 Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bhe@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 20D79369C4 Date: Wed, 17 May 2017 11:39:45 +0800 From: Baoquan He To: Dave Young Cc: linux-kernel@vger.kernel.org, bp@alien8.de, bhsharma@redhat.com, rja@hpe.com, Matt Fleming , Ard Biesheuvel , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Thomas Garnier , Kees Cook , x86@kernel.org, linux-efi@vger.kernel.org Subject: Re: [PATCH v3] x86/efi: Correct ident mapping of efi old_map when kalsr enabled Message-ID: <20170517033945.GD29117@x1> References: <1494647799-20600-1-git-send-email-bhe@redhat.com> <20170517025513.GA9988@dhcp-128-65.nay.redhat.com> <20170517033529.GC29117@x1> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170517033529.GC29117@x1> User-Agent: Mutt/1.7.0 (2016-08-17) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Wed, 17 May 2017 03:39:50 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/17/17 at 11:35am, Baoquan He wrote: > On 05/17/17 at 10:55am, Dave Young wrote: > > Hi, Baoquan > > > arch/x86/platform/efi/efi_64.c | 69 +++++++++++++++++++++++++++++++++++++----- > > > 1 file changed, 61 insertions(+), 8 deletions(-) > > > > > > diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c > > > index c488625..c9dffec 100644 > > > --- a/arch/x86/platform/efi/efi_64.c > > > +++ b/arch/x86/platform/efi/efi_64.c > > > @@ -71,11 +71,13 @@ static void __init early_code_mapping_set_exec(int executable) > > > > > > pgd_t * __init efi_call_phys_prolog(void) > > > { > > > - unsigned long vaddress; > > > - pgd_t *save_pgd; > > > + unsigned long vaddr, addr_pgd, addr_p4d, addr_pud; > > > + pgd_t *save_pgd, *pgd_k, *pgd_efi; > > > + p4d_t *p4d, *p4d_k, *p4d_efi; > > > + pud_t *pud; > > > > > > int pgd; > > > - int n_pgds; > > > + int n_pgds, i, j; > > > > > > if (!efi_enabled(EFI_OLD_MEMMAP)) { > > > save_pgd = (pgd_t *)read_cr3(); > > > @@ -88,10 +90,44 @@ pgd_t * __init efi_call_phys_prolog(void) > > > n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE); > > > save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL); > > > > > > + /* > > > + * Build 1:1 ident mapping for old_map usage. It needs to be noticed > > > + * that PAGE_OFFSET is PGDIR_SIZE aligned with KASLR disabled, while > > > + * PUD_SIZE ALIGNED with KASLR enabled. So for a given physical > > > + * address X, the pud_index(X) != pud_index(__va(X)), we can only copy > > > + * pud entry of __va(X) to fill in pud entry of X to build 1:1 mapping > > > + * . Means here we can only reuse pmd table of direct mapping. > > > + */ > > > for (pgd = 0; pgd < n_pgds; pgd++) { > > > - save_pgd[pgd] = *pgd_offset_k(pgd * PGDIR_SIZE); > > > - vaddress = (unsigned long)__va(pgd * PGDIR_SIZE); > > > - set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), *pgd_offset_k(vaddress)); > > > + addr_pgd = (unsigned long)(pgd * PGDIR_SIZE); > > > + vaddr = (unsigned long)__va(pgd * PGDIR_SIZE); > > > + pgd_efi = pgd_offset_k(addr_pgd); > > > + save_pgd[pgd] = *pgd_efi; > > > + p4d = p4d_alloc(&init_mm, pgd_efi, addr_pgd); > > > + > > > + if (!p4d) { > > > + pr_err("Failed to allocate p4d table \n"); > > > + goto out; > > > + } > > > + for(i=0; i > > > There is code style issue here and other for loop later.. > > Oops, I forget running scripts/checkpatch.pl to check patch. Will change > and post v4. May post with sgi v4 fix about the sgi uv mmioh region ~~~~~~sgi uv > issue, have discussed with HPE SGI developer about that. > > Thanks for pointing it out! > > Thanks > Baoquan > > > > > > + addr_p4d = addr_pgd + i * P4D_SIZE; > > > + p4d_efi = p4d + p4d_index(addr_p4d); > > > + pud = pud_alloc(&init_mm, p4d_efi, addr_p4d); > > > + if (!pud) { > > > + pr_err("Failed to allocate pud table \n"); > > > + goto out; > > > + } > > > + for(j=0; j > > + addr_pud = addr_p4d + j * PUD_SIZE; > > > + if (addr_pud > (max_pfn << PAGE_SHIFT)) > > > + break; > > > + vaddr = (unsigned long)__va(addr_pud); > > > + > > > + pgd_k = pgd_offset_k(vaddr); > > > + p4d_k = p4d_offset(pgd_k, vaddr); > > > + pud[j] = *pud_offset(p4d_k, vaddr); > > > + } > > > + } > > > } > > > out: > > > __flush_tlb_all(); > > > @@ -104,8 +140,11 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd) > > > /* > > > * After the lock is released, the original page table is restored. > > > */ > > > - int pgd_idx; > > > + int pgd_idx, i; > > > int nr_pgds; > > > + pgd_t *pgd; > > > + p4d_t *p4d; > > > + pud_t *pud; > > > > > > if (!efi_enabled(EFI_OLD_MEMMAP)) { > > > write_cr3((unsigned long)save_pgd); > > > @@ -115,9 +154,23 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd) > > > > > > nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE); > > > > > > - for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++) > > > + for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++) { > > > + pgd = pgd_offset_k(pgd_idx * PGDIR_SIZE); > > > set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]); > > > > > > + if (!(pgd_val(*pgd) & _PAGE_PRESENT)) > > > + continue; > > > + for(i=0; i > > + p4d = p4d_offset(pgd, pgd_idx * PGDIR_SIZE + i * P4D_SIZE); > > > + if (!(p4d_val(*p4d) & _PAGE_PRESENT)) > > > + continue; > > > + pud = (pud_t*)p4d_page_vaddr(*p4d); > > > + pud_free(&init_mm, pud); > > > + } > > > + p4d = (p4d_t*)pgd_page_vaddr(*pgd); > > > + p4d_free(&init_mm, p4d); > > > + } > > > + > > > kfree(save_pgd); > > > > > > __flush_tlb_all(); > > > -- > > > 2.5.5 > > > > > > > Thanks > > Dave