From: tip-bot for Joerg Roedel <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: jgross@suse.com, boris.ostrovsky@oracle.com,
dave.hansen@intel.com, pavel@ucw.cz, gregkh@linuxfoundation.org,
will.deacon@arm.com, brgerst@gmail.com, tglx@linutronix.de,
hpa@zytor.com, luto@kernel.org, jroedel@suse.de,
mingo@kernel.org, eduval@amazon.com, jkosina@suse.cz,
linux-kernel@vger.kernel.org, llong@redhat.com,
torvalds@linux-foundation.org, bp@alien8.de, aarcange@redhat.com,
jpoimboe@redhat.com, dhgutteridge@sympatico.ca,
peterz@infradead.org, dvlasenk@redhat.com,
David.Laight@aculab.com
Subject: [tip:x86/pti] x86/pgtable/pae: Use separate kernel PMDs for user page-table
Date: Thu, 19 Jul 2018 16:35:18 -0700 [thread overview]
Message-ID: <tip-f59dbe9ca6707eb7ffd0e24359085651c2d7df48@git.kernel.org> (raw)
In-Reply-To: <1531906876-13451-33-git-send-email-joro@8bytes.org>
Commit-ID: f59dbe9ca6707eb7ffd0e24359085651c2d7df48
Gitweb: https://git.kernel.org/tip/f59dbe9ca6707eb7ffd0e24359085651c2d7df48
Author: Joerg Roedel <jroedel@suse.de>
AuthorDate: Wed, 18 Jul 2018 11:41:09 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 20 Jul 2018 01:11:46 +0200
x86/pgtable/pae: Use separate kernel PMDs for user page-table
When PTI is enabled, separate kernel PMDs in the user page-table are
required to map the per-process LDT for user-space.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-33-git-send-email-joro@8bytes.org
---
arch/x86/mm/pgtable.c | 100 ++++++++++++++++++++++++++++++++++++++++----------
1 file changed, 81 insertions(+), 19 deletions(-)
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index db6fb7740bf7..8e4e63d46d81 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -182,6 +182,14 @@ static void pgd_dtor(pgd_t *pgd)
*/
#define PREALLOCATED_PMDS UNSHARED_PTRS_PER_PGD
+/*
+ * We allocate separate PMDs for the kernel part of the user page-table
+ * when PTI is enabled. We need them to map the per-process LDT into the
+ * user-space page-table.
+ */
+#define PREALLOCATED_USER_PMDS (static_cpu_has(X86_FEATURE_PTI) ? \
+ KERNEL_PGD_PTRS : 0)
+
void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
{
paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
@@ -202,14 +210,14 @@ void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
/* No need to prepopulate any pagetable entries in non-PAE modes. */
#define PREALLOCATED_PMDS 0
-
+#define PREALLOCATED_USER_PMDS 0
#endif /* CONFIG_X86_PAE */
-static void free_pmds(struct mm_struct *mm, pmd_t *pmds[])
+static void free_pmds(struct mm_struct *mm, pmd_t *pmds[], int count)
{
int i;
- for(i = 0; i < PREALLOCATED_PMDS; i++)
+ for (i = 0; i < count; i++)
if (pmds[i]) {
pgtable_pmd_page_dtor(virt_to_page(pmds[i]));
free_page((unsigned long)pmds[i]);
@@ -217,7 +225,7 @@ static void free_pmds(struct mm_struct *mm, pmd_t *pmds[])
}
}
-static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
+static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[], int count)
{
int i;
bool failed = false;
@@ -226,7 +234,7 @@ static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
if (mm == &init_mm)
gfp &= ~__GFP_ACCOUNT;
- for(i = 0; i < PREALLOCATED_PMDS; i++) {
+ for (i = 0; i < count; i++) {
pmd_t *pmd = (pmd_t *)__get_free_page(gfp);
if (!pmd)
failed = true;
@@ -241,7 +249,7 @@ static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
}
if (failed) {
- free_pmds(mm, pmds);
+ free_pmds(mm, pmds, count);
return -ENOMEM;
}
@@ -254,23 +262,38 @@ static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
* preallocate which never got a corresponding vma will need to be
* freed manually.
*/
+static void mop_up_one_pmd(struct mm_struct *mm, pgd_t *pgdp)
+{
+ pgd_t pgd = *pgdp;
+
+ if (pgd_val(pgd) != 0) {
+ pmd_t *pmd = (pmd_t *)pgd_page_vaddr(pgd);
+
+ *pgdp = native_make_pgd(0);
+
+ paravirt_release_pmd(pgd_val(pgd) >> PAGE_SHIFT);
+ pmd_free(mm, pmd);
+ mm_dec_nr_pmds(mm);
+ }
+}
+
static void pgd_mop_up_pmds(struct mm_struct *mm, pgd_t *pgdp)
{
int i;
- for(i = 0; i < PREALLOCATED_PMDS; i++) {
- pgd_t pgd = pgdp[i];
+ for (i = 0; i < PREALLOCATED_PMDS; i++)
+ mop_up_one_pmd(mm, &pgdp[i]);
- if (pgd_val(pgd) != 0) {
- pmd_t *pmd = (pmd_t *)pgd_page_vaddr(pgd);
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
- pgdp[i] = native_make_pgd(0);
+ if (!static_cpu_has(X86_FEATURE_PTI))
+ return;
- paravirt_release_pmd(pgd_val(pgd) >> PAGE_SHIFT);
- pmd_free(mm, pmd);
- mm_dec_nr_pmds(mm);
- }
- }
+ pgdp = kernel_to_user_pgdp(pgdp);
+
+ for (i = 0; i < PREALLOCATED_USER_PMDS; i++)
+ mop_up_one_pmd(mm, &pgdp[i + KERNEL_PGD_BOUNDARY]);
+#endif
}
static void pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmds[])
@@ -296,6 +319,38 @@ static void pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmds[])
}
}
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
+static void pgd_prepopulate_user_pmd(struct mm_struct *mm,
+ pgd_t *k_pgd, pmd_t *pmds[])
+{
+ pgd_t *s_pgd = kernel_to_user_pgdp(swapper_pg_dir);
+ pgd_t *u_pgd = kernel_to_user_pgdp(k_pgd);
+ p4d_t *u_p4d;
+ pud_t *u_pud;
+ int i;
+
+ u_p4d = p4d_offset(u_pgd, 0);
+ u_pud = pud_offset(u_p4d, 0);
+
+ s_pgd += KERNEL_PGD_BOUNDARY;
+ u_pud += KERNEL_PGD_BOUNDARY;
+
+ for (i = 0; i < PREALLOCATED_USER_PMDS; i++, u_pud++, s_pgd++) {
+ pmd_t *pmd = pmds[i];
+
+ memcpy(pmd, (pmd_t *)pgd_page_vaddr(*s_pgd),
+ sizeof(pmd_t) * PTRS_PER_PMD);
+
+ pud_populate(mm, u_pud, pmd);
+ }
+
+}
+#else
+static void pgd_prepopulate_user_pmd(struct mm_struct *mm,
+ pgd_t *k_pgd, pmd_t *pmds[])
+{
+}
+#endif
/*
* Xen paravirt assumes pgd table should be in one page. 64 bit kernel also
* assumes that pgd should be in one page.
@@ -376,6 +431,7 @@ static inline void _pgd_free(pgd_t *pgd)
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd;
+ pmd_t *u_pmds[PREALLOCATED_USER_PMDS];
pmd_t *pmds[PREALLOCATED_PMDS];
pgd = _pgd_alloc();
@@ -385,12 +441,15 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
mm->pgd = pgd;
- if (preallocate_pmds(mm, pmds) != 0)
+ if (preallocate_pmds(mm, pmds, PREALLOCATED_PMDS) != 0)
goto out_free_pgd;
- if (paravirt_pgd_alloc(mm) != 0)
+ if (preallocate_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS) != 0)
goto out_free_pmds;
+ if (paravirt_pgd_alloc(mm) != 0)
+ goto out_free_user_pmds;
+
/*
* Make sure that pre-populating the pmds is atomic with
* respect to anything walking the pgd_list, so that they
@@ -400,13 +459,16 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
pgd_ctor(mm, pgd);
pgd_prepopulate_pmd(mm, pgd, pmds);
+ pgd_prepopulate_user_pmd(mm, pgd, u_pmds);
spin_unlock(&pgd_lock);
return pgd;
+out_free_user_pmds:
+ free_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS);
out_free_pmds:
- free_pmds(mm, pmds);
+ free_pmds(mm, pmds, PREALLOCATED_PMDS);
out_free_pgd:
_pgd_free(pgd);
out:
next prev parent reply other threads:[~2018-07-19 23:36 UTC|newest]
Thread overview: 96+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-18 9:40 [PATCH 00/39 v8] PTI support for x86-32 Joerg Roedel
2018-07-18 9:40 ` [PATCH 01/39] x86/asm-offsets: Move TSS_sp0 and TSS_sp1 to asm-offsets.c Joerg Roedel
2018-07-19 23:18 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 02/39] x86/entry/32: Rename TSS_sysenter_sp0 to TSS_entry2task_stack Joerg Roedel
2018-07-19 23:19 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 03/39] x86/entry/32: Load task stack from x86_tss.sp1 in SYSENTER handler Joerg Roedel
2018-07-19 23:19 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 04/39] x86/entry/32: Put ESPFIX code into a macro Joerg Roedel
2018-07-19 23:20 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 05/39] x86/entry/32: Unshare NMI return path Joerg Roedel
2018-07-19 23:21 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 06/39] x86/entry/32: Split off return-to-kernel path Joerg Roedel
2018-07-19 23:21 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 07/39] x86/entry/32: Enter the kernel via trampoline stack Joerg Roedel
2018-07-18 18:09 ` Brian Gerst
2018-07-19 20:52 ` Thomas Gleixner
2018-07-19 23:22 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 08/39] x86/entry/32: Leave " Joerg Roedel
2018-07-19 23:22 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 09/39] x86/entry/32: Introduce SAVE_ALL_NMI and RESTORE_ALL_NMI Joerg Roedel
2018-07-19 23:23 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 10/39] x86/entry/32: Handle Entry from Kernel-Mode on Entry-Stack Joerg Roedel
2018-07-19 23:23 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-10-12 18:29 ` [PATCH 10/39] " Jan Kiszka
2018-10-13 9:54 ` [PATCH] x86/entry/32: Fix setup of CS high bits Jan Kiszka
2018-10-13 15:12 ` Andy Lutomirski
2018-10-15 13:08 ` Jan Kiszka
2018-10-15 13:14 ` David Laight
2018-10-15 13:18 ` Jan Kiszka
2018-10-15 13:29 ` David Laight
2018-10-15 9:10 ` Joerg Roedel
2018-10-15 14:09 ` [PATCH v2] " Jan Kiszka
2018-10-15 15:09 ` [tip:x86/urgent] x86/entry/32: Clear the " tip-bot for Jan Kiszka
2018-10-18 6:21 ` tip-bot for Jan Kiszka
2018-07-18 9:40 ` [PATCH 11/39] x86/entry/32: Simplify debug entry point Joerg Roedel
2018-07-19 23:24 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 12/39] x86/entry/32: Add PTI cr3 switch to non-NMI entry/exit points Joerg Roedel
2018-07-19 23:24 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 13/39] x86/entry/32: Add PTI cr3 switches to NMI handler code Joerg Roedel
2018-07-19 23:25 ` [tip:x86/pti] x86/entry/32: Add PTI CR3 " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 14/39] x86/entry: Rename update_sp0 to update_task_stack Joerg Roedel
2018-07-19 23:25 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 15/39] x86/pgtable: Rename pti_set_user_pgd to pti_set_user_pgtbl Joerg Roedel
2018-07-19 23:26 ` [tip:x86/pti] x86/pgtable: Rename pti_set_user_pgd() to pti_set_user_pgtbl() tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 16/39] x86/pgtable/pae: Unshare kernel PMDs when PTI is enabled Joerg Roedel
2018-07-19 23:26 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 17/39] x86/pgtable/32: Allocate 8k page-tables " Joerg Roedel
2018-07-19 23:27 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 18/39] x86/pgtable: Move pgdp kernel/user conversion functions to pgtable.h Joerg Roedel
2018-07-19 23:27 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 19/39] x86/pgtable: Move pti_set_user_pgtbl() " Joerg Roedel
2018-07-19 23:28 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 20/39] x86/pgtable: Move two more functions from pgtable_64.h " Joerg Roedel
2018-07-19 23:28 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 21/39] x86/mm/pae: Populate valid user PGD entries Joerg Roedel
2018-07-19 23:29 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:40 ` [PATCH 22/39] x86/mm/pae: Populate the user page-table with user pgd's Joerg Roedel
2018-07-19 23:30 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 23/39] x86/mm/legacy: " Joerg Roedel
2018-07-19 23:30 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 24/39] x86/mm/pti: Add an overflow check to pti_clone_pmds() Joerg Roedel
2018-07-19 23:31 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 25/39] x86/mm/pti: Define X86_CR3_PTI_PCID_USER_BIT on x86_32 Joerg Roedel
2018-07-19 23:31 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 26/39] x86/mm/pti: Clone CPU_ENTRY_AREA on PMD level " Joerg Roedel
2018-07-19 23:32 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 27/39] x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit Joerg Roedel
2018-07-19 23:32 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 28/39] x86/mm/pti: Keep permissions when cloning kernel text in pti_clone_kernel_text() Joerg Roedel
2018-07-19 23:33 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 29/39] x86/mm/pti: Introduce pti_finalize() Joerg Roedel
2018-07-19 23:33 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 30/39] x86/mm/pti: Clone entry-text again in pti_finalize() Joerg Roedel
2018-07-19 23:34 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 31/39] x86/mm/dump_pagetables: Define INIT_PGD Joerg Roedel
2018-07-19 23:34 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 32/39] x86/pgtable/pae: Use separate kernel PMDs for user page-table Joerg Roedel
2018-07-19 23:35 ` tip-bot for Joerg Roedel [this message]
2018-10-05 14:06 ` Arnd Bergmann
2018-07-18 9:41 ` [PATCH 33/39] x86/ldt: Reserve address-space range on 32 bit for the LDT Joerg Roedel
2018-07-19 23:35 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 34/39] x86/ldt: Define LDT_END_ADDR Joerg Roedel
2018-07-19 23:36 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 35/39] x86/ldt: Split out sanity check in map_ldt_struct() Joerg Roedel
2018-07-19 23:36 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 36/39] x86/ldt: Enable LDT user-mapping for PAE Joerg Roedel
2018-07-19 23:37 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 37/39] x86/pti: Allow CONFIG_PAGE_TABLE_ISOLATION for x86_32 Joerg Roedel
2018-07-19 23:37 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 38/39] x86/mm/pti: Add Warning when booting on a PCID capable CPU Joerg Roedel
2018-07-19 23:38 ` [tip:x86/pti] " tip-bot for Joerg Roedel
2018-07-18 9:41 ` [PATCH 39/39] x86/entry/32: Add debug code to check entry/exit cr3 Joerg Roedel
2018-07-19 23:38 ` [tip:x86/pti] x86/entry/32: Add debug code to check entry/exit CR3 tip-bot for Joerg Roedel
2018-07-18 11:59 ` [PATCH 00/39 v8] PTI support for x86-32 Pavel Machek
2018-07-19 23:21 ` Thomas Gleixner
2018-07-20 7:59 ` Joerg Roedel
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