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Message-Id: <200810311153.14644.rusty@rustcorp.com.au>
Date: Fri, 31 Oct 2008 11:53:14 +1100
From: Rusty Russell <rusty@...tcorp.com.au>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: lguest <lguest@...abs.org>, linux-kernel@...r.kernel.org
Subject: [PULL] lguest boot fixes, example launcher fixes.
The following changes since commit 65fc716fa673cf98fb5887180fd3c52ca0371198:
Linus Torvalds (1):
Merge git://git.kernel.org/.../sam/kbuild-fixes
are available in the git repository at:
ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus.git master
Rusty Russell (3):
lguest: fix example launcher compile after moved asm-x86 dir.
lguest: fix early_ioremap.
lguest: fix irq vectors.
Documentation/lguest/Makefile | 2 +-
Documentation/lguest/lguest.c | 2 +-
arch/x86/lguest/boot.c | 32 ++++++++++++++++++++------------
3 files changed, 22 insertions(+), 14 deletions(-)
diff --git a/Documentation/lguest/Makefile b/Documentation/lguest/Makefile
index bac037e..725eef8 100644
--- a/Documentation/lguest/Makefile
+++ b/Documentation/lguest/Makefile
@@ -1,5 +1,5 @@
# This creates the demonstration utility "lguest" which runs a Linux guest.
-CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include
+CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include
LDLIBS:=-lz
all: lguest
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index da86fd5..8045206 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -44,7 +44,7 @@
#include "linux/virtio_console.h"
#include "linux/virtio_rng.h"
#include "linux/virtio_ring.h"
-#include "asm-x86/bootparam.h"
+#include "asm/bootparam.h"
/*L:110 We can ignore the 39 include files we need for this program, but I do
* want to draw attention to the use of kernel-style types.
*
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 48ee4f9..a5d8e1a 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -367,10 +367,9 @@ static void lguest_cpuid(unsigned int *ax, unsigned int *bx,
* lazily after a task switch, and Linux uses that gratefully, but wouldn't a
* name like "FPUTRAP bit" be a little less cryptic?
*
- * We store cr0 (and cr3) locally, because the Host never changes it. The
- * Guest sometimes wants to read it and we'd prefer not to bother the Host
- * unnecessarily. */
-static unsigned long current_cr0, current_cr3;
+ * We store cr0 locally because the Host never changes it. The Guest sometimes
+ * wants to read it and we'd prefer not to bother the Host unnecessarily. */
+static unsigned long current_cr0;
static void lguest_write_cr0(unsigned long val)
{
lazy_hcall(LHCALL_TS, val & X86_CR0_TS, 0, 0);
@@ -399,17 +398,23 @@ static unsigned long lguest_read_cr2(void)
return lguest_data.cr2;
}
+/* See lguest_set_pte() below. */
+static bool cr3_changed = false;
+
/* cr3 is the current toplevel pagetable page: the principle is the same as
- * cr0. Keep a local copy, and tell the Host when it changes. */
+ * cr0. Keep a local copy, and tell the Host when it changes. The only
+ * difference is that our local copy is in lguest_data because the Host needs
+ * to set it upon our initial hypercall. */
static void lguest_write_cr3(unsigned long cr3)
{
+ lguest_data.pgdir = cr3;
lazy_hcall(LHCALL_NEW_PGTABLE, cr3, 0, 0);
- current_cr3 = cr3;
+ cr3_changed = true;
}
static unsigned long lguest_read_cr3(void)
{
- return current_cr3;
+ return lguest_data.pgdir;
}
/* cr4 is used to enable and disable PGE, but we don't care. */
@@ -498,13 +503,13 @@ static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
* to forget all of them. Fortunately, this is very rare.
*
* ... except in early boot when the kernel sets up the initial pagetables,
- * which makes booting astonishingly slow. So we don't even tell the Host
- * anything changed until we've done the first page table switch. */
+ * which makes booting astonishingly slow: 1.83 seconds! So we don't even tell
+ * the Host anything changed until we've done the first page table switch,
+ * which brings boot back to 0.25 seconds. */
static void lguest_set_pte(pte_t *ptep, pte_t pteval)
{
*ptep = pteval;
- /* Don't bother with hypercall before initial setup. */
- if (current_cr3)
+ if (cr3_changed)
lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
}
@@ -521,7 +526,7 @@ static void lguest_set_pte(pte_t *ptep, pte_t pteval)
static void lguest_flush_tlb_single(unsigned long addr)
{
/* Simply set it to zero: if it was not, it will fault back in. */
- lazy_hcall(LHCALL_SET_PTE, current_cr3, addr, 0);
+ lazy_hcall(LHCALL_SET_PTE, lguest_data.pgdir, addr, 0);
}
/* This is what happens after the Guest has removed a large number of entries.
@@ -581,6 +586,9 @@ static void __init lguest_init_IRQ(void)
for (i = 0; i < LGUEST_IRQS; i++) {
int vector = FIRST_EXTERNAL_VECTOR + i;
+ /* Some systems map "vectors" to interrupts weirdly. Lguest has
+ * a straightforward 1 to 1 mapping, so force that here. */
+ __get_cpu_var(vector_irq)[vector] = i;
if (vector != SYSCALL_VECTOR) {
set_intr_gate(vector, interrupt[vector]);
set_irq_chip_and_handler_name(i, &lguest_irq_controller,
--
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