From: Dave Hansen <dave.hansen@linux.intel.com>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, dave.hansen@linux.intel.com,
moritz.lipp@iaik.tugraz.at, daniel.gruss@iaik.tugraz.at,
michael.schwarz@iaik.tugraz.at, luto@kernel.org,
torvalds@linux-foundation.org, keescook@google.com,
hughd@google.com, x86@kernel.org
Subject: [PATCH 10/23] x86, kaiser: make sure static PGDs are 8k in size
Date: Tue, 31 Oct 2017 15:32:05 -0700 [thread overview]
Message-ID: <20171031223205.951EFCB6@viggo.jf.intel.com> (raw)
In-Reply-To: <20171031223146.6B47C861@viggo.jf.intel.com>
We have a few PGDs that come out of the kernel binary instead of being
allocated dynamically. Before this patch, they are all 8k-aligned,
but we also need them to be 8k in *size*e
The original KAISER patch did not do this. It probably just lucked out
that it did not trample over data after the last PGD.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kees Cook <keescook@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: x86@kernel.org
---
b/arch/x86/kernel/head_64.S | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff -puN arch/x86/kernel/head_64.S~kaiser-head_S-pgds-need-8k-too arch/x86/kernel/head_64.S
--- a/arch/x86/kernel/head_64.S~kaiser-head_S-pgds-need-8k-too 2017-10-31 15:03:53.866279568 -0700
+++ b/arch/x86/kernel/head_64.S 2017-10-31 15:03:53.870279757 -0700
@@ -340,11 +340,24 @@ GLOBAL(early_recursion_flag)
GLOBAL(name)
#ifdef CONFIG_KAISER
+/*
+ * Each PGD needs to be 8k long and 8k aligned. We do not
+ * ever go out to userspace with these, so we do not
+ * strictly *need* the second page, but this allows us to
+ * have a single set_pgd() implementation that does not
+ * need to worry about whether it has 4k or 8k to work
+ * with.
+ *
+ * This ensures PGDs are 8k long:
+ */
+#define KAISER_USER_PGD_FILL 512
+/* This ensures they are 8k-aligned: */
#define NEXT_PGD_PAGE(name) \
.balign 2 * PAGE_SIZE; \
GLOBAL(name)
#else
#define NEXT_PGD_PAGE(name) NEXT_PAGE(name)
+#define KAISER_USER_PGD_FILL 0
#endif
/* Automate the creation of 1 to 1 mapping pmd entries */
@@ -363,6 +376,7 @@ NEXT_PGD_PAGE(early_top_pgt)
#else
.quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC
#endif
+ .fill KAISER_USER_PGD_FILL,8,0
NEXT_PAGE(early_dynamic_pgts)
.fill 512*EARLY_DYNAMIC_PAGE_TABLES,8,0
@@ -372,6 +386,7 @@ NEXT_PAGE(early_dynamic_pgts)
#ifndef CONFIG_XEN
NEXT_PGD_PAGE(init_top_pgt)
.fill 512,8,0
+ .fill KAISER_USER_PGD_FILL,8,0
#else
NEXT_PGD_PAGE(init_top_pgt)
.quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC
@@ -380,6 +395,7 @@ NEXT_PGD_PAGE(init_top_pgt)
.org init_top_pgt + PGD_START_KERNEL*8, 0
/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
.quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC
+ .fill KAISER_USER_PGD_FILL,8,0
NEXT_PAGE(level3_ident_pgt)
.quad level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC
_
next prev parent reply other threads:[~2017-10-31 22:35 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-31 22:31 [PATCH 00/23] KAISER: unmap most of the kernel from userspace page tables Dave Hansen
2017-10-31 22:31 ` [PATCH 01/23] x86, kaiser: prepare assembly for entry/exit CR3 switching Dave Hansen
2017-11-01 0:43 ` Brian Gerst
2017-11-01 1:08 ` Dave Hansen
2017-11-01 18:18 ` Borislav Petkov
2017-11-01 18:27 ` Dave Hansen
2017-11-01 20:42 ` Borislav Petkov
2017-11-01 21:01 ` Thomas Gleixner
2017-11-01 22:58 ` Dave Hansen
2017-10-31 22:31 ` [PATCH 02/23] x86, kaiser: do not set _PAGE_USER for init_mm page tables Dave Hansen
2017-11-01 21:11 ` Thomas Gleixner
2017-11-01 21:24 ` Andy Lutomirski
2017-11-01 21:28 ` Thomas Gleixner
2017-11-01 21:52 ` Dave Hansen
2017-11-01 22:11 ` Thomas Gleixner
2017-11-01 22:12 ` Linus Torvalds
2017-11-01 22:20 ` Thomas Gleixner
2017-11-01 22:45 ` Kees Cook
2017-11-02 7:10 ` Andy Lutomirski
2017-11-02 11:33 ` Thomas Gleixner
2017-11-02 11:59 ` Andy Lutomirski
2017-11-02 12:56 ` Thomas Gleixner
2017-11-02 16:38 ` Dave Hansen
2017-11-02 18:19 ` Andy Lutomirski
2017-11-02 18:24 ` Thomas Gleixner
2017-11-02 18:24 ` Linus Torvalds
2017-11-02 18:40 ` Thomas Gleixner
2017-11-02 18:57 ` Linus Torvalds
2017-11-02 21:41 ` Thomas Gleixner
2017-11-02 7:07 ` Andy Lutomirski
2017-11-02 11:21 ` Thomas Gleixner
2017-10-31 22:31 ` [PATCH 03/23] x86, kaiser: disable global pages Dave Hansen
2017-11-01 21:18 ` Thomas Gleixner
2017-11-01 22:12 ` Dave Hansen
2017-11-01 22:28 ` Thomas Gleixner
2017-10-31 22:31 ` [PATCH 04/23] x86, tlb: make CR4-based TLB flushes more robust Dave Hansen
2017-11-01 8:01 ` Andy Lutomirski
2017-11-01 10:11 ` Kirill A. Shutemov
2017-11-01 10:38 ` Andy Lutomirski
2017-11-01 10:56 ` Kirill A. Shutemov
2017-11-01 11:18 ` Andy Lutomirski
2017-11-01 22:21 ` Dave Hansen
2017-11-01 21:25 ` Thomas Gleixner
2017-11-01 22:24 ` Dave Hansen
2017-11-01 22:30 ` Thomas Gleixner
2017-10-31 22:31 ` [PATCH 05/23] x86, mm: document X86_CR4_PGE toggling behavior Dave Hansen
2017-10-31 23:31 ` Kees Cook
2017-10-31 22:31 ` [PATCH 06/23] x86, kaiser: introduce user-mapped percpu areas Dave Hansen
2017-11-01 21:47 ` Thomas Gleixner
2017-10-31 22:31 ` [PATCH 07/23] x86, kaiser: unmap kernel from userspace page tables (core patch) Dave Hansen
2017-10-31 22:32 ` [PATCH 08/23] x86, kaiser: only populate shadow page tables for userspace Dave Hansen
2017-10-31 23:35 ` Kees Cook
2017-10-31 22:32 ` [PATCH 09/23] x86, kaiser: allow NX to be set in p4d/pgd Dave Hansen
2017-10-31 22:32 ` Dave Hansen [this message]
2017-10-31 22:32 ` [PATCH 11/23] x86, kaiser: map GDT into user page tables Dave Hansen
2017-10-31 22:32 ` [PATCH 12/23] x86, kaiser: map dynamically-allocated LDTs Dave Hansen
2017-11-01 8:00 ` Andy Lutomirski
2017-11-01 8:06 ` Ingo Molnar
2017-10-31 22:32 ` [PATCH 13/23] x86, kaiser: map espfix structures Dave Hansen
2017-10-31 22:32 ` [PATCH 14/23] x86, kaiser: map entry stack variables Dave Hansen
2017-10-31 22:32 ` [PATCH 15/23] x86, kaiser: map trace interrupt entry Dave Hansen
2017-10-31 22:32 ` [PATCH 16/23] x86, kaiser: map debug IDT tables Dave Hansen
2017-10-31 22:32 ` [PATCH 17/23] x86, kaiser: map virtually-addressed performance monitoring buffers Dave Hansen
2017-10-31 22:32 ` [PATCH 18/23] x86, mm: Move CR3 construction functions Dave Hansen
2017-10-31 22:32 ` [PATCH 19/23] x86, mm: remove hard-coded ASID limit checks Dave Hansen
2017-10-31 22:32 ` [PATCH 20/23] x86, mm: put mmu-to-h/w ASID translation in one place Dave Hansen
2017-10-31 22:32 ` [PATCH 21/23] x86, pcid, kaiser: allow flushing for future ASID switches Dave Hansen
2017-11-01 8:03 ` Andy Lutomirski
2017-11-01 14:17 ` Dave Hansen
2017-11-01 20:31 ` Andy Lutomirski
2017-11-01 20:59 ` Dave Hansen
2017-11-01 21:04 ` Andy Lutomirski
2017-11-01 21:06 ` Dave Hansen
2017-10-31 22:32 ` [PATCH 22/23] x86, kaiser: use PCID feature to make user and kernel switches faster Dave Hansen
2017-10-31 22:32 ` [PATCH 23/23] x86, kaiser: add Kconfig Dave Hansen
2017-10-31 23:59 ` Kees Cook
2017-11-01 9:07 ` Borislav Petkov
2017-10-31 23:27 ` [PATCH 00/23] KAISER: unmap most of the kernel from userspace page tables Linus Torvalds
2017-10-31 23:44 ` Dave Hansen
2017-11-01 0:21 ` Dave Hansen
2017-11-01 7:59 ` Andy Lutomirski
2017-11-01 16:08 ` Linus Torvalds
2017-11-01 17:31 ` Dave Hansen
2017-11-01 17:58 ` Randy Dunlap
2017-11-01 18:27 ` Linus Torvalds
2017-11-01 18:46 ` Dave Hansen
2017-11-01 19:05 ` Linus Torvalds
2017-11-01 20:33 ` Andy Lutomirski
2017-11-02 7:32 ` Andy Lutomirski
2017-11-02 7:54 ` Andy Lutomirski
2017-11-01 15:53 ` Dave Hansen
2017-11-01 8:54 ` Ingo Molnar
2017-11-01 14:09 ` Thomas Gleixner
2017-11-01 22:14 ` Dave Hansen
2017-11-01 22:28 ` Linus Torvalds
2017-11-02 8:03 ` Peter Zijlstra
2017-11-03 11:07 ` Kirill A. Shutemov
2017-11-02 19:01 ` Will Deacon
2017-11-02 19:38 ` Dave Hansen
2017-11-03 13:41 ` Will Deacon
2017-11-22 16:19 ` Pavel Machek
2017-11-23 10:47 ` Pavel Machek
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20171031223205.951EFCB6@viggo.jf.intel.com \
--to=dave.hansen@linux.intel.com \
--cc=daniel.gruss@iaik.tugraz.at \
--cc=hughd@google.com \
--cc=keescook@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=michael.schwarz@iaik.tugraz.at \
--cc=moritz.lipp@iaik.tugraz.at \
--cc=torvalds@linux-foundation.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).