5.10-stable patches

added patches:
	revert-drm-add-a-locked-version-of-drm_is_current_master.patch

diff --git a/queue-5.10/revert-drm-add-a-locked-version-of-drm_is_current_master.patch b/queue-5.10/revert-drm-add-a-locked-version-of-drm_is_current_master.patch
new file mode 100644 (file)
index 0000000..6f1b73d
--- /dev/null
+++ b/queue-5.10/revert-drm-add-a-locked-version-of-drm_is_current_master.patch
@@ -0,0 +1,166 @@
+From f54b3ca7ea1e5e02f481cf4ca54568e57bd66086 Mon Sep 17 00:00:00 2001
+From: Daniel Vetter <daniel.vetter@ffwll.ch>
+Date: Tue, 22 Jun 2021 09:54:09 +0200
+Subject: Revert "drm: add a locked version of drm_is_current_master"
+
+From: Daniel Vetter <daniel.vetter@ffwll.ch>
+
+commit f54b3ca7ea1e5e02f481cf4ca54568e57bd66086 upstream.
+
+This reverts commit 1815d9c86e3090477fbde066ff314a7e9721ee0f.
+
+Unfortunately this inverts the locking hierarchy, so back to the
+drawing board. Full lockdep splat below:
+
+======================================================
+WARNING: possible circular locking dependency detected
+5.13.0-rc7-CI-CI_DRM_10254+ #1 Not tainted
+------------------------------------------------------
+kms_frontbuffer/1087 is trying to acquire lock:
+ffff88810dcd01a8 (&dev->master_mutex){+.+.}-{3:3}, at: drm_is_current_master+0x1b/0x40
+but task is already holding lock:
+ffff88810dcd0488 (&dev->mode_config.mutex){+.+.}-{3:3}, at: drm_mode_getconnector+0x1c6/0x4a0
+which lock already depends on the new lock.
+the existing dependency chain (in reverse order) is:
+-> #2 (&dev->mode_config.mutex){+.+.}-{3:3}:
+       __mutex_lock+0xab/0x970
+       drm_client_modeset_probe+0x22e/0xca0
+       __drm_fb_helper_initial_config_and_unlock+0x42/0x540
+       intel_fbdev_initial_config+0xf/0x20 [i915]
+       async_run_entry_fn+0x28/0x130
+       process_one_work+0x26d/0x5c0
+       worker_thread+0x37/0x380
+       kthread+0x144/0x170
+       ret_from_fork+0x1f/0x30
+-> #1 (&client->modeset_mutex){+.+.}-{3:3}:
+       __mutex_lock+0xab/0x970
+       drm_client_modeset_commit_locked+0x1c/0x180
+       drm_client_modeset_commit+0x1c/0x40
+       __drm_fb_helper_restore_fbdev_mode_unlocked+0x88/0xb0
+       drm_fb_helper_set_par+0x34/0x40
+       intel_fbdev_set_par+0x11/0x40 [i915]
+       fbcon_init+0x270/0x4f0
+       visual_init+0xc6/0x130
+       do_bind_con_driver+0x1e5/0x2d0
+       do_take_over_console+0x10e/0x180
+       do_fbcon_takeover+0x53/0xb0
+       register_framebuffer+0x22d/0x310
+       __drm_fb_helper_initial_config_and_unlock+0x36c/0x540
+       intel_fbdev_initial_config+0xf/0x20 [i915]
+       async_run_entry_fn+0x28/0x130
+       process_one_work+0x26d/0x5c0
+       worker_thread+0x37/0x380
+       kthread+0x144/0x170
+       ret_from_fork+0x1f/0x30
+-> #0 (&dev->master_mutex){+.+.}-{3:3}:
+       __lock_acquire+0x151e/0x2590
+       lock_acquire+0xd1/0x3d0
+       __mutex_lock+0xab/0x970
+       drm_is_current_master+0x1b/0x40
+       drm_mode_getconnector+0x37e/0x4a0
+       drm_ioctl_kernel+0xa8/0xf0
+       drm_ioctl+0x1e8/0x390
+       __x64_sys_ioctl+0x6a/0xa0
+       do_syscall_64+0x39/0xb0
+       entry_SYSCALL_64_after_hwframe+0x44/0xae
+other info that might help us debug this:
+Chain exists of: &dev->master_mutex --> &client->modeset_mutex --> &dev->mode_config.mutex
+ Possible unsafe locking scenario:
+       CPU0                    CPU1
+       ----                    ----
+  lock(&dev->mode_config.mutex);
+                               lock(&client->modeset_mutex);
+                               lock(&dev->mode_config.mutex);
+  lock(&dev->master_mutex);
+---
+ drivers/gpu/drm/drm_auth.c |   51 ++++++++++++++++-----------------------------
+ 1 file changed, 19 insertions(+), 32 deletions(-)
+
+--- a/drivers/gpu/drm/drm_auth.c
++++ b/drivers/gpu/drm/drm_auth.c
+@@ -61,35 +61,6 @@
+  * trusted clients.
+  */
+ 
+-static bool drm_is_current_master_locked(struct drm_file *fpriv)
+-{
+-      lockdep_assert_held_once(&fpriv->master->dev->master_mutex);
+-
+-      return fpriv->is_master && drm_lease_owner(fpriv->master) == fpriv->minor->dev->master;
+-}
+-
+-/**
+- * drm_is_current_master - checks whether @priv is the current master
+- * @fpriv: DRM file private
+- *
+- * Checks whether @fpriv is current master on its device. This decides whether a
+- * client is allowed to run DRM_MASTER IOCTLs.
+- *
+- * Most of the modern IOCTL which require DRM_MASTER are for kernel modesetting
+- * - the current master is assumed to own the non-shareable display hardware.
+- */
+-bool drm_is_current_master(struct drm_file *fpriv)
+-{
+-      bool ret;
+-
+-      mutex_lock(&fpriv->master->dev->master_mutex);
+-      ret = drm_is_current_master_locked(fpriv);
+-      mutex_unlock(&fpriv->master->dev->master_mutex);
+-
+-      return ret;
+-}
+-EXPORT_SYMBOL(drm_is_current_master);
+-
+ int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv)
+ {
+       struct drm_auth *auth = data;
+@@ -252,7 +223,7 @@ int drm_setmaster_ioctl(struct drm_devic
+       if (ret)
+               goto out_unlock;
+ 
+-      if (drm_is_current_master_locked(file_priv))
++      if (drm_is_current_master(file_priv))
+               goto out_unlock;
+ 
+       if (dev->master) {
+@@ -301,7 +272,7 @@ int drm_dropmaster_ioctl(struct drm_devi
+       if (ret)
+               goto out_unlock;
+ 
+-      if (!drm_is_current_master_locked(file_priv)) {
++      if (!drm_is_current_master(file_priv)) {
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+@@ -350,7 +321,7 @@ void drm_master_release(struct drm_file
+       if (file_priv->magic)
+               idr_remove(&file_priv->master->magic_map, file_priv->magic);
+ 
+-      if (!drm_is_current_master_locked(file_priv))
++      if (!drm_is_current_master(file_priv))
+               goto out;
+ 
+       drm_legacy_lock_master_cleanup(dev, master);
+@@ -372,6 +343,22 @@ out:
+ }
+ 
+ /**
++ * drm_is_current_master - checks whether @priv is the current master
++ * @fpriv: DRM file private
++ *
++ * Checks whether @fpriv is current master on its device. This decides whether a
++ * client is allowed to run DRM_MASTER IOCTLs.
++ *
++ * Most of the modern IOCTL which require DRM_MASTER are for kernel modesetting
++ * - the current master is assumed to own the non-shareable display hardware.
++ */
++bool drm_is_current_master(struct drm_file *fpriv)
++{
++      return fpriv->is_master && drm_lease_owner(fpriv->master) == fpriv->minor->dev->master;
++}
++EXPORT_SYMBOL(drm_is_current_master);
++
++/**
+  * drm_master_get - reference a master pointer
+  * @master: &struct drm_master
+  *

diff --git a/queue-5.10/series b/queue-5.10/series
index 867e8ec7a9c674799ecb981ef100eefeeba8dfed..0b328bce239639bb5ed908c90aadc7cd6c1c96d9 100644 (file)
--- a/queue-5.10/series
+++ b/queue-5.10/series
@@ -93,3 +93,4 @@ mm-futex-fix-shared-futex-pgoff-on-shmem-huge-page.patch
 kvm-svm-call-sev-guest-decommission-if-asid-binding-fails.patch
 swiotlb-manipulate-orig_addr-when-tlb_addr-has-offset.patch
 netfs-fix-test-for-whether-we-can-skip-read-when-writing-beyond-eof.patch
+revert-drm-add-a-locked-version-of-drm_is_current_master.patch