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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2008-04-01 08:22:26 +0400
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2008-04-01 08:22:26 +0400
commit399f486286f44d55c4fff0e9cc5d712f2b443489 (patch)
tree0c2820b3e04232eaa96f08c1057b87728fb3e7a4 /drivers/lguest/hypercalls.c
parent481419ec9fbdf3f4ec5389c7e91a81b4a7ebee8d (diff)
parenta9edadbf790d72adf6ebed476cb5caf7743e7e4a (diff)
downloadlinux-399f486286f44d55c4fff0e9cc5d712f2b443489.tar.xz
Merge master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus
Diffstat (limited to 'drivers/lguest/hypercalls.c')
-rw-r--r--drivers/lguest/hypercalls.c11
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c
index 0f2cb4fd7c69..54d66f05fefa 100644
--- a/drivers/lguest/hypercalls.c
+++ b/drivers/lguest/hypercalls.c
@@ -29,7 +29,7 @@
#include "lg.h"
/*H:120 This is the core hypercall routine: where the Guest gets what it wants.
- * Or gets killed. Or, in the case of LHCALL_CRASH, both. */
+ * Or gets killed. Or, in the case of LHCALL_SHUTDOWN, both. */
static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
{
switch (args->arg0) {
@@ -190,6 +190,13 @@ static void initialize(struct lg_cpu *cpu)
* pagetable. */
guest_pagetable_clear_all(cpu);
}
+/*:*/
+
+/*M:013 If a Guest reads from a page (so creates a mapping) that it has never
+ * written to, and then the Launcher writes to it (ie. the output of a virtual
+ * device), the Guest will still see the old page. In practice, this never
+ * happens: why would the Guest read a page which it has never written to? But
+ * a similar scenario might one day bite us, so it's worth mentioning. :*/
/*H:100
* Hypercalls
@@ -227,7 +234,7 @@ void do_hypercalls(struct lg_cpu *cpu)
* However, if we are signalled or the Guest sends I/O to the
* Launcher, the run_guest() loop will exit without running the
* Guest. When it comes back it would try to re-run the
- * hypercall. */
+ * hypercall. Finding that bug sucked. */
cpu->hcall = NULL;
}
}