diff mbox

[v2,2/2] Revert "spapr: fix memory hot-unplugging"

Message ID 20170608172743.10132-3-lvivier@redhat.com
State New
Headers show

Commit Message

Laurent Vivier June 8, 2017, 5:27 p.m. UTC
This reverts commit fe6824d12642b005c69123ecf8631f9b13553f8b.

Conflicts hw/ppc/spapr_drc.c, because get_index() has been renamed
spapr_get_index().

This didn't fix the problem. Once the hotplug has been started
some memory is allocated and some structures are allocated.
We don't free it when we ignore the unplug, and we can't because
they can be in use by the kernel.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 hw/ppc/spapr_drc.c         | 20 +++-----------------
 include/hw/ppc/spapr_drc.h |  1 -
 2 files changed, 3 insertions(+), 18 deletions(-)

Comments

David Gibson June 9, 2017, 2:35 a.m. UTC | #1
On Thu, Jun 08, 2017 at 07:27:43PM +0200, Laurent Vivier wrote:
> This reverts commit fe6824d12642b005c69123ecf8631f9b13553f8b.
> 
> Conflicts hw/ppc/spapr_drc.c, because get_index() has been renamed
> spapr_get_index().
> 
> This didn't fix the problem. Once the hotplug has been started
> some memory is allocated and some structures are allocated.
> We don't free it when we ignore the unplug, and we can't because
> they can be in use by the kernel.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>

Heh.  I've just been looking at awaiting_allocation_skippable and
trying - but failing - to work out what it accomplishes.  Applied to
ppc-for-2.10.

> ---
>  hw/ppc/spapr_drc.c         | 20 +++-----------------
>  include/hw/ppc/spapr_drc.h |  1 -
>  2 files changed, 3 insertions(+), 18 deletions(-)
> 
> diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c
> index 39e7f30..7605977 100644
> --- a/hw/ppc/spapr_drc.c
> +++ b/hw/ppc/spapr_drc.c
> @@ -140,17 +140,6 @@ static uint32_t set_allocation_state(sPAPRDRConnector *drc,
>          if (!drc->dev) {
>              return RTAS_OUT_NO_SUCH_INDICATOR;
>          }
> -        if (drc->awaiting_release && drc->awaiting_allocation) {
> -            /* kernel is acknowledging a previous hotplug event
> -             * while we are already removing it.
> -             * it's safe to ignore awaiting_allocation here since we know the
> -             * situation is predicated on the guest either already having done
> -             * so (boot-time hotplug), or never being able to acquire in the
> -             * first place (hotplug followed by immediate unplug).
> -             */
> -            drc->awaiting_allocation_skippable = true;
> -            return RTAS_OUT_NO_SUCH_INDICATOR;
> -        }
>      }
>  
>      if (spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PCI) {
> @@ -401,11 +390,9 @@ static void detach(sPAPRDRConnector *drc, DeviceState *d, Error **errp)
>      }
>  
>      if (drc->awaiting_allocation) {
> -        if (!drc->awaiting_allocation_skippable) {
> -            drc->awaiting_release = true;
> -            trace_spapr_drc_awaiting_allocation(spapr_drc_index(drc));
> -            return;
> -        }
> +        drc->awaiting_release = true;
> +        trace_spapr_drc_awaiting_allocation(spapr_drc_index(drc));
> +        return;
>      }
>  
>      drc->indicator_state = SPAPR_DR_INDICATOR_STATE_INACTIVE;
> @@ -428,7 +415,6 @@ static void detach(sPAPRDRConnector *drc, DeviceState *d, Error **errp)
>      }
>  
>      drc->awaiting_release = false;
> -    drc->awaiting_allocation_skippable = false;
>      g_free(drc->fdt);
>      drc->fdt = NULL;
>      drc->fdt_start_offset = 0;
> diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h
> index c88e1be..84b58f0 100644
> --- a/include/hw/ppc/spapr_drc.h
> +++ b/include/hw/ppc/spapr_drc.h
> @@ -200,7 +200,6 @@ typedef struct sPAPRDRConnector {
>      bool awaiting_release;
>      bool signalled;
>      bool awaiting_allocation;
> -    bool awaiting_allocation_skippable;
>  
>      /* device pointer, via link property */
>      DeviceState *dev;
diff mbox

Patch

diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c
index 39e7f30..7605977 100644
--- a/hw/ppc/spapr_drc.c
+++ b/hw/ppc/spapr_drc.c
@@ -140,17 +140,6 @@  static uint32_t set_allocation_state(sPAPRDRConnector *drc,
         if (!drc->dev) {
             return RTAS_OUT_NO_SUCH_INDICATOR;
         }
-        if (drc->awaiting_release && drc->awaiting_allocation) {
-            /* kernel is acknowledging a previous hotplug event
-             * while we are already removing it.
-             * it's safe to ignore awaiting_allocation here since we know the
-             * situation is predicated on the guest either already having done
-             * so (boot-time hotplug), or never being able to acquire in the
-             * first place (hotplug followed by immediate unplug).
-             */
-            drc->awaiting_allocation_skippable = true;
-            return RTAS_OUT_NO_SUCH_INDICATOR;
-        }
     }
 
     if (spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PCI) {
@@ -401,11 +390,9 @@  static void detach(sPAPRDRConnector *drc, DeviceState *d, Error **errp)
     }
 
     if (drc->awaiting_allocation) {
-        if (!drc->awaiting_allocation_skippable) {
-            drc->awaiting_release = true;
-            trace_spapr_drc_awaiting_allocation(spapr_drc_index(drc));
-            return;
-        }
+        drc->awaiting_release = true;
+        trace_spapr_drc_awaiting_allocation(spapr_drc_index(drc));
+        return;
     }
 
     drc->indicator_state = SPAPR_DR_INDICATOR_STATE_INACTIVE;
@@ -428,7 +415,6 @@  static void detach(sPAPRDRConnector *drc, DeviceState *d, Error **errp)
     }
 
     drc->awaiting_release = false;
-    drc->awaiting_allocation_skippable = false;
     g_free(drc->fdt);
     drc->fdt = NULL;
     drc->fdt_start_offset = 0;
diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h
index c88e1be..84b58f0 100644
--- a/include/hw/ppc/spapr_drc.h
+++ b/include/hw/ppc/spapr_drc.h
@@ -200,7 +200,6 @@  typedef struct sPAPRDRConnector {
     bool awaiting_release;
     bool signalled;
     bool awaiting_allocation;
-    bool awaiting_allocation_skippable;
 
     /* device pointer, via link property */
     DeviceState *dev;