From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 46/67] mm: ptdump: reduce level numbers by 1 in note_page() Date: Mon, 03 Feb 2020 17:36:38 -0800 Message-ID: <20200204013638.Zs2G-ZbS8%akpm@linux-foundation.org> References: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:37508 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726992AbgBDBgm (ORCPT ); Mon, 3 Feb 2020 20:36:42 -0500 In-Reply-To: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, alex@ghiti.fr, aou@eecs.berkeley.edu, ard.biesheuvel@linaro.org, arnd@arndb.de, benh@kernel.crashing.org, borntraeger@de.ibm.com, bp@alien8.de, catalin.marinas@arm.com, dave.hansen@linux.intel.com, davem@davemloft.net, gor@linux.ibm.com, heiko.carstens@de.ibm.com, hpa@zytor.com, james.morse@arm.com, jglisse@redhat.com, jhogan@kernel.org, kan.liang@linux.intel.com, linux-mm@kvack.org, linux@armlinux.org.uk, luto@kernel.org, mark.rutland@arm.com, mingo@redhat.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, paul.burton@mips.com, paul.walmsley@sifive.com, paulus@samba.org, peterz@infradead.org, ralf@linux-mips.org, steven.price@arm.com, tglx@linutronix.de, torvalds@linux-foundation.org, vgupta@synopsys.com, will@kernel.org, zong.li@sifive.com From: Steven Price Subject: mm: ptdump: reduce level numbers by 1 in note_page() Rather than having to increment the 'depth' number by 1 in ptdump_hole(), let's change the meaning of 'level' in note_page() since that makes the code simplier. Note that for x86, the level numbers were previously increased by 1 in commit 45dcd2091363 ("x86/mm/dump_pagetables: Fix printout of p4d level") and the comment "Bit 7 has a different meaning" was not updated, so this change also makes the code match the comment again. Link: http://lkml.kernel.org/r/20191218162402.45610-24-steven.price@arm.com Signed-off-by: Steven Price Reviewed-by: Catalin Marinas Cc: Albert Ou Cc: Alexandre Ghiti Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Christian Borntraeger Cc: Dave Hansen Cc: David S. Miller Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: James Hogan Cc: James Morse Cc: Jerome Glisse Cc: "Liang, Kan" Cc: Mark Rutland Cc: Michael Ellerman Cc: Paul Burton Cc: Paul Mackerras Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Ralf Baechle Cc: Russell King Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Cc: Zong Li Signed-off-by: Andrew Morton --- arch/arm64/mm/dump.c | 6 +++--- arch/x86/mm/dump_pagetables.c | 19 ++++++++++--------- include/linux/ptdump.h | 1 + mm/ptdump.c | 16 ++++++++-------- 4 files changed, 22 insertions(+), 20 deletions(-) --- a/arch/arm64/mm/dump.c~mm-ptdump-reduce-level-numbers-by-1-in-note_page +++ a/arch/arm64/mm/dump.c @@ -176,8 +176,7 @@ struct pg_level { }; static struct pg_level pg_level[] = { - { - }, { /* pgd */ + { /* pgd */ .name = "PGD", .bits = pte_bits, .num = ARRAY_SIZE(pte_bits), @@ -257,7 +256,7 @@ static void note_page(struct ptdump_stat if (level >= 0) prot = val & pg_level[level].mask; - if (!st->level) { + if (st->level == -1) { st->level = level; st->current_prot = prot; st->start_address = addr; @@ -351,6 +350,7 @@ void ptdump_check_wx(void) { 0, NULL}, { -1, NULL}, }, + .level = -1, .check_wx = true, .ptdump = { .note_page = note_page, --- a/arch/x86/mm/dump_pagetables.c~mm-ptdump-reduce-level-numbers-by-1-in-note_page +++ a/arch/x86/mm/dump_pagetables.c @@ -180,7 +180,7 @@ static struct addr_marker address_marker static void printk_prot(struct seq_file *m, pgprotval_t pr, int level, bool dmsg) { static const char * const level_name[] = - { "cr3", "pgd", "p4d", "pud", "pmd", "pte" }; + { "pgd", "p4d", "pud", "pmd", "pte" }; if (!(pr & _PAGE_PRESENT)) { /* Not present */ @@ -204,12 +204,12 @@ static void printk_prot(struct seq_file pt_dump_cont_printf(m, dmsg, " "); /* Bit 7 has a different meaning on level 3 vs 4 */ - if (level <= 4 && pr & _PAGE_PSE) + if (level <= 3 && pr & _PAGE_PSE) pt_dump_cont_printf(m, dmsg, "PSE "); else pt_dump_cont_printf(m, dmsg, " "); - if ((level == 5 && pr & _PAGE_PAT) || - ((level == 4 || level == 3) && pr & _PAGE_PAT_LARGE)) + if ((level == 4 && pr & _PAGE_PAT) || + ((level == 3 || level == 2) && pr & _PAGE_PAT_LARGE)) pt_dump_cont_printf(m, dmsg, "PAT "); else pt_dump_cont_printf(m, dmsg, " "); @@ -271,15 +271,15 @@ static void note_page(struct ptdump_stat new_prot = val & PTE_FLAGS_MASK; - if (level > 1) { - new_eff = effective_prot(st->prot_levels[level - 2], + if (level > 0) { + new_eff = effective_prot(st->prot_levels[level - 1], new_prot); } else { new_eff = new_prot; } - if (level > 0) - st->prot_levels[level - 1] = new_eff; + if (level >= 0) + st->prot_levels[level] = new_eff; /* * If we have a "break" in the series, we need to flush the state that @@ -289,7 +289,7 @@ static void note_page(struct ptdump_stat cur = st->current_prot; eff = st->effective_prot; - if (!st->level) { + if (st->level == -1) { /* First entry */ st->current_prot = new_prot; st->effective_prot = new_eff; @@ -380,6 +380,7 @@ static void ptdump_walk_pgd_level_core(s .note_page = note_page, .range = ptdump_ranges }, + .level = -1, .to_dmesg = dmesg, .check_wx = checkwx, .seq = m --- a/include/linux/ptdump.h~mm-ptdump-reduce-level-numbers-by-1-in-note_page +++ a/include/linux/ptdump.h @@ -11,6 +11,7 @@ struct ptdump_range { }; struct ptdump_state { + /* level is 0:PGD to 4:PTE, or -1 if unknown */ void (*note_page)(struct ptdump_state *st, unsigned long addr, int level, unsigned long val); const struct ptdump_range *range; --- a/mm/ptdump.c~mm-ptdump-reduce-level-numbers-by-1-in-note_page +++ a/mm/ptdump.c @@ -17,7 +17,7 @@ static inline int note_kasan_page_table( { struct ptdump_state *st = walk->private; - st->note_page(st, addr, 5, pte_val(kasan_early_shadow_pte[0])); + st->note_page(st, addr, 4, pte_val(kasan_early_shadow_pte[0])); walk->action = ACTION_CONTINUE; @@ -37,7 +37,7 @@ static int ptdump_pgd_entry(pgd_t *pgd, #endif if (pgd_leaf(val)) - st->note_page(st, addr, 1, pgd_val(val)); + st->note_page(st, addr, 0, pgd_val(val)); return 0; } @@ -54,7 +54,7 @@ static int ptdump_p4d_entry(p4d_t *p4d, #endif if (p4d_leaf(val)) - st->note_page(st, addr, 2, p4d_val(val)); + st->note_page(st, addr, 1, p4d_val(val)); return 0; } @@ -71,7 +71,7 @@ static int ptdump_pud_entry(pud_t *pud, #endif if (pud_leaf(val)) - st->note_page(st, addr, 3, pud_val(val)); + st->note_page(st, addr, 2, pud_val(val)); return 0; } @@ -88,7 +88,7 @@ static int ptdump_pmd_entry(pmd_t *pmd, #endif if (pmd_leaf(val)) - st->note_page(st, addr, 4, pmd_val(val)); + st->note_page(st, addr, 3, pmd_val(val)); return 0; } @@ -98,7 +98,7 @@ static int ptdump_pte_entry(pte_t *pte, { struct ptdump_state *st = walk->private; - st->note_page(st, addr, 5, pte_val(READ_ONCE(*pte))); + st->note_page(st, addr, 4, pte_val(READ_ONCE(*pte))); return 0; } @@ -108,7 +108,7 @@ static int ptdump_hole(unsigned long add { struct ptdump_state *st = walk->private; - st->note_page(st, addr, depth + 1, 0); + st->note_page(st, addr, depth, 0); return 0; } @@ -135,5 +135,5 @@ void ptdump_walk_pgd(struct ptdump_state up_read(&mm->mmap_sem); /* Flush out the last page */ - st->note_page(st, 0, 0, 0); + st->note_page(st, 0, -1, 0); } _