From: Ingo Molnar <mingo@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>,
Andy Lutomirski <luto@amacapital.net>,
Thomas Gleixner <tglx@linutronix.de>,
"H . Peter Anvin" <hpa@zytor.com>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: [PATCH 05/24] x86/mm/kaiser: Allow NX poison to be set in p4d/pgd
Date: Mon, 27 Nov 2017 11:49:04 +0100 [thread overview]
Message-ID: <20171127104923.14378-6-mingo@kernel.org> (raw)
In-Reply-To: <20171127104923.14378-1-mingo@kernel.org>
From: Dave Hansen <dave.hansen@linux.intel.com>
The user portion of the kernel page tables use the NX bit to
poison them for userspace. But, that trips the p4d/pgd_bad()
checks. Make sure it does not do that.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Cc: michael.schwarz@iaik.tugraz.at
Cc: moritz.lipp@iaik.tugraz.at
Cc: richard.fellner@student.tugraz.at
Link: https://lkml.kernel.org/r/20171123003448.C6AB3575@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/pgtable.h | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index d3901124143f..9cceaf6c0405 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -846,7 +846,12 @@ static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
static inline int p4d_bad(p4d_t p4d)
{
- return (p4d_flags(p4d) & ~(_KERNPG_TABLE | _PAGE_USER)) != 0;
+ unsigned long ignore_flags = _KERNPG_TABLE | _PAGE_USER;
+
+ if (IS_ENABLED(CONFIG_KAISER))
+ ignore_flags |= _PAGE_NX;
+
+ return (p4d_flags(p4d) & ~ignore_flags) != 0;
}
#endif /* CONFIG_PGTABLE_LEVELS > 3 */
@@ -880,7 +885,12 @@ static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
static inline int pgd_bad(pgd_t pgd)
{
- return (pgd_flags(pgd) & ~_PAGE_USER) != _KERNPG_TABLE;
+ unsigned long ignore_flags = _PAGE_USER;
+
+ if (IS_ENABLED(CONFIG_KAISER))
+ ignore_flags |= _PAGE_NX;
+
+ return (pgd_flags(pgd) & ~ignore_flags) != _KERNPG_TABLE;
}
static inline int pgd_none(pgd_t pgd)
--
2.14.1
next prev parent reply other threads:[~2017-11-27 10:57 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-27 10:48 [PATCH 00/24] x86/mm: Add KAISER support Ingo Molnar
2017-11-27 10:49 ` [PATCH 01/24] x86/mm/kaiser: Disable global pages by default with KAISER Ingo Molnar
2017-11-27 10:49 ` [PATCH 02/24] x86/mm/kaiser: Prepare the x86/entry assembly code for entry/exit CR3 switching Ingo Molnar
2017-11-27 17:31 ` Peter Zijlstra
2017-11-27 17:33 ` Thomas Gleixner
2017-11-27 21:00 ` Peter Zijlstra
2017-11-27 10:49 ` [PATCH 03/24] x86/mm/kaiser: Introduce user-mapped per-CPU areas Ingo Molnar
2017-11-27 10:49 ` [PATCH 04/24] x86/mm/kaiser: Unmap kernel mappings from userspace page tables, core patch Ingo Molnar
2017-11-27 15:39 ` Peter Zijlstra
2017-11-27 17:04 ` Borislav Petkov
2017-11-27 19:17 ` Dave Hansen
2017-11-28 10:34 ` Peter Zijlstra
2017-11-27 10:49 ` Ingo Molnar [this message]
2017-11-27 10:49 ` [PATCH 06/24] x86/mm/kaiser: Make sure the static PGDs are 8k in size Ingo Molnar
2017-11-27 10:49 ` [PATCH 07/24] x86/mm/kaiser: Map the CPU entry area Ingo Molnar
2017-11-27 10:49 ` [PATCH 08/24] x86/mm/kaiser: Map the dynamically-allocated LDTs Ingo Molnar
2017-11-29 22:03 ` [08/24] " Guenter Roeck
2017-11-27 10:49 ` [PATCH 09/24] x86/mm/kaiser: Map the espfix structures Ingo Molnar
2017-11-27 10:49 ` [PATCH 10/24] x86/mm/kaiser: Map the entry stack variables Ingo Molnar
2017-11-27 17:22 ` Peter Zijlstra
2017-11-27 17:32 ` Thomas Gleixner
2017-11-27 21:00 ` Peter Zijlstra
2017-11-27 17:29 ` Peter Zijlstra
2017-11-27 17:32 ` Thomas Gleixner
2017-11-27 10:49 ` [PATCH 11/24] x86/mm/kaiser: Map virtually-addressed performance monitoring buffers Ingo Molnar
2017-11-27 10:49 ` [PATCH 12/24] x86/mm: Move the CR3 construction functions to tlbflush.h Ingo Molnar
2017-11-27 10:49 ` [PATCH 13/24] x86/mm: Remove hard-coded ASID limit checks Ingo Molnar
2017-11-27 10:49 ` [PATCH 14/24] x86/mm: Put MMU-to-h/w ASID translation in one place Ingo Molnar
2017-11-27 10:49 ` [PATCH 15/24] x86/mm: Allow flushing for future ASID switches Ingo Molnar
2017-11-28 5:16 ` Andy Lutomirski
2017-11-28 7:32 ` Dave Hansen
2017-11-28 16:39 ` Peter Zijlstra
2017-11-28 16:48 ` Peter Zijlstra
2017-11-28 18:13 ` Dave Hansen
2017-11-28 19:05 ` Peter Zijlstra
2017-11-28 19:36 ` Peter Zijlstra
2017-11-28 20:34 ` Andy Lutomirski
2017-11-28 20:39 ` Peter Zijlstra
2017-11-28 20:45 ` Peter Zijlstra
2017-11-30 15:40 ` Peter Zijlstra
2017-11-30 15:42 ` Andy Lutomirski
2017-11-30 15:44 ` Peter Zijlstra
2017-11-30 15:51 ` Dave Hansen
2017-11-30 16:18 ` Peter Zijlstra
2017-11-30 18:44 ` Dave Hansen
2017-11-30 18:48 ` Andy Lutomirski
2017-11-30 18:53 ` Dave Hansen
2017-11-30 20:01 ` Peter Zijlstra
2017-11-30 21:51 ` Andy Lutomirski
2017-11-30 18:55 ` Peter Zijlstra
2017-11-30 19:00 ` Dave Hansen
2017-11-30 19:20 ` Peter Zijlstra
2017-11-27 10:49 ` [PATCH 16/24] x86/mm/kaiser: Use PCID feature to make user and kernel switches faster Ingo Molnar
2017-11-28 5:22 ` Andy Lutomirski
2017-11-28 7:52 ` Dave Hansen
2017-11-27 10:49 ` [PATCH 17/24] x86/mm/kaiser: Disable native VSYSCALL Ingo Molnar
2017-11-27 10:49 ` [PATCH 18/24] x86/mm/kaiser: Add Kconfig Ingo Molnar
2017-11-27 10:49 ` [PATCH 19/24] x86/mm/kaiser: Respect disabled CPU features Ingo Molnar
2017-11-27 10:49 ` [PATCH 20/24] x86/mm/kaiser: Simplify disabling of global pages Ingo Molnar
2017-11-27 10:49 ` [PATCH 21/24] x86/mm/dump_pagetables: Check Kaiser shadow page table for WX pages Ingo Molnar
2017-11-27 10:49 ` [PATCH 22/24] x86/mm/debug_pagetables: Allow dumping current pagetables Ingo Molnar
2017-11-27 10:49 ` [PATCH 23/24] x86/mm/kaiser: Add boot time disable switch Ingo Molnar
2017-11-27 10:49 ` [PATCH 24/24] x86/mm/kaiser: Use the other page_table_lock pattern Ingo Molnar
2017-11-27 13:51 ` [PATCH 00/24] x86/mm: Add KAISER support Borislav Petkov
2017-11-27 13:57 ` Thomas Gleixner
2017-11-27 13:59 ` Borislav Petkov
2017-11-27 14:03 ` Ingo Molnar
2017-11-27 14:08 ` Ingo Molnar
2017-11-27 19:43 ` Linus Torvalds
2017-11-27 20:01 ` Linus Torvalds
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