Re: [PATCH] drm: Restore drm_file->is_master

Hi

On Thu, Aug 7, 2014 at 3:04 PM, Chris Wilson chris@chris-wilson.co.uk wrote:

Despite the claims of

commit 48ba813701eb14b3008edefef4a0789b328e278c Author: David Herrmann dh.herrmann@gmail.com Date: Tue Jul 22 18:46:09 2014 +0200

drm: drop redundant drm_file->is_master

drm_file->is_master is not synomous with having drm_file->master == drm_file->minor->master. This is because drm_file->master is the same for all drm_files of the same generation and so when there is a master, every drm_file believes itself to be the master. Confusion ensues and things go pear shaped when one file is closed and there is no master anymore.

Uagh, embarrassing. A revert is fine with me, but I'll try to review your patch once I get home.

Thanks David

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=82283 Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Alex Deucher alexander.deucher@amd.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: David Herrmann dh.herrmann@gmail.com

---

drivers/gpu/drm/drm_drv.c | 5 ++--- drivers/gpu/drm/drm_fops.c | 12 ++++++------ include/drm/drmP.h | 3 ++- 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index a1863d8..76cdb51 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -198,6 +198,7 @@ int drm_setmaster_ioctl(struct drm_device *dev, void *data, if (unlikely(ret != 0)) drm_master_put(&file_priv->minor->master); }

•   file_priv->is_master = ret == 0;
  
  

out_unlock: mutex_unlock(&dev->master_mutex); @@ -213,13 +214,11 @@ int drm_dropmaster_ioctl(struct drm_device *dev, void *data, if (!drm_is_master(file_priv)) goto out_unlock;

•   if (!file_priv->minor->master)
  

•           goto out_unlock;
  

•   ret = 0;
    if (dev->driver->master_drop)
            dev->driver->master_drop(dev, file_priv, false);
    drm_master_put(&file_priv->minor->master);
  

•   file_priv->is_master = false;
  
  

out_unlock: mutex_unlock(&dev->master_mutex); diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index c0166ba..083f7b9 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -196,6 +196,7 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor)

            /* take another reference for the copy in the local file priv */
            priv->master = drm_master_get(priv->minor->master);

•           priv->is_master = true;
            priv->authenticated = 1;
  
            if (dev->driver->master_create) {
  

@@ -434,12 +435,11 @@ int drm_release(struct inode *inode, struct file *filp) } mutex_unlock(&dev->struct_mutex);

•           if (file_priv->minor->master == file_priv->master) {
  

•                   /* drop the reference held my the minor */
  

•                   if (dev->driver->master_drop)
  

•                           dev->driver->master_drop(dev, file_priv, true);
  

•                   drm_master_put(&file_priv->minor->master);
  

•           }
  

•           /* drop the reference held my the minor */
  

•           if (dev->driver->master_drop)
  

•                   dev->driver->master_drop(dev, file_priv, true);
  

•           drm_master_put(&file_priv->minor->master);
  

•           file_priv->is_master = false;
    }
  
    /* drop the master reference held by the file priv */
  

diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 0ffce5c..70a6598 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -378,6 +378,7 @@ struct drm_prime_file_private {

/** File private data */ struct drm_file {

•   bool is_master:1;
    unsigned authenticated :1;
    /* true when the client has asked us to expose stereo 3D mode flags */
    unsigned stereo_allowed :1;
  

@@ -1177,7 +1178,7 @@ static inline bool drm_is_primary_client(const struct drm_file *file_priv) */ static inline bool drm_is_master(const struct drm_file *file) {

•   return file->master && file->master == file->minor->master;
  

•   return file->is_master;
  

}

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1.9.1