Re: [PATCH 3/7] vmw_balloon: fix inflation of 64-bit GFNs
at 11:21 AM, Greg Kroah-Hartman wrote:
> On Wed, Jun 13, 2018 at 04:03:55AM -0700, Nadav Amit wrote:
>> When balloon batching is not supported by the hypervisor, the guest
>> frame number (GFN) must fit in 32-bit. However, due to a bug, this check
>> was mistakenly ignored. In practice, when total RAM is greater than
>> 16TB, the balloon does not work currently, making this bug unlikely to
>> happen.
>>
>> Fixes: ef0f8f112984 ("VMware balloon: partially inline
>> vmballoon_reserve_page.")
>
> Why have a bugfix as the 3rd patch of the series? Please put it first,
> so that it can get into Linus's tree sooner.
>
> Also, no need to line-wrap this, and drop the blank line.
>
> And finally, does this need to go to the stable kernels? If so, please
> add the correct line for that.
I will fix the message. Patches 3-7 deal with minor bugs, some of which have
been there since day one, so I didn’t put a “Fixes” tag.
I’ll follow your direction and put patches 1-2 at the end.
Re: [PATCH 3/7] vmw_balloon: fix inflation of 64-bit GFNs
On Wed, Jun 13, 2018 at 04:03:55AM -0700, Nadav Amit wrote:
> When balloon batching is not supported by the hypervisor, the guest
> frame number (GFN) must fit in 32-bit. However, due to a bug, this check
> was mistakenly ignored. In practice, when total RAM is greater than
> 16TB, the balloon does not work currently, making this bug unlikely to
> happen.
>
> Fixes: ef0f8f112984 ("VMware balloon: partially inline
> vmballoon_reserve_page.")
>
Why have a bugfix as the 3rd patch of the series? Please put it first,
so that it can get into Linus's tree sooner.
Also, no need to line-wrap this, and drop the blank line.
And finally, does this need to go to the stable kernels? If so, please
add the correct line for that.
thanks,
greg k-h
[PATCH 3/7] vmw_balloon: fix inflation of 64-bit GFNs
When balloon batching is not supported by the hypervisor, the guest
frame number (GFN) must fit in 32-bit. However, due to a bug, this check
was mistakenly ignored. In practice, when total RAM is greater than
16TB, the balloon does not work currently, making this bug unlikely to
happen.
Fixes: ef0f8f112984 ("VMware balloon: partially inline
vmballoon_reserve_page.")
Reviewed-by: Xavier Deguillard
Signed-off-by: Nadav Amit
---
drivers/misc/vmw_balloon.c | 13 +++--
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c
index a73b5d64403a..496607a9046a 100644
--- a/drivers/misc/vmw_balloon.c
+++ b/drivers/misc/vmw_balloon.c
@@ -448,7 +448,7 @@ static int vmballoon_send_lock_page(struct vmballoon *b,
unsigned long pfn,
pfn32 = (u32)pfn;
if (pfn32 != pfn)
- return -1;
+ return -EINVAL;
STATS_INC(b->stats.lock[false]);
@@ -458,7 +458,7 @@ static int vmballoon_send_lock_page(struct vmballoon *b,
unsigned long pfn,
pr_debug("%s - ppn %lx, hv returns %ld\n", __func__, pfn, status);
STATS_INC(b->stats.lock_fail[false]);
- return 1;
+ return -EIO;
}
static int vmballoon_send_batched_lock(struct vmballoon *b,
@@ -595,11 +595,12 @@ static int vmballoon_lock_page(struct vmballoon *b,
unsigned int num_pages,
locked = vmballoon_send_lock_page(b, page_to_pfn(page), &hv_status,
target);
- if (locked > 0) {
+ if (locked) {
STATS_INC(b->stats.refused_alloc[false]);
- if (hv_status == VMW_BALLOON_ERROR_RESET ||
- hv_status == VMW_BALLOON_ERROR_PPN_NOTNEEDED) {
+ if (locked == -EIO &&
+ (hv_status == VMW_BALLOON_ERROR_RESET ||
+hv_status == VMW_BALLOON_ERROR_PPN_NOTNEEDED)) {
vmballoon_free_page(page, false);
return -EIO;
}
@@ -615,7 +616,7 @@ static int vmballoon_lock_page(struct vmballoon *b,
unsigned int num_pages,
} else {
vmballoon_free_page(page, false);
}
- return -EIO;
+ return locked;
}
/* track allocated page */
--
2.17.0
