/* Copyright 2008 - 2016 Freescale Semiconductor, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Freescale Semiconductor nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* ALTERNATIVELY, this software may be distributed under the terms of the
* GNU General Public License ("GPL") as published by the Free Software
* Foundation, either version 2 of that License or (at your option) any
* later version.
*
* THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __FSL_BMAN_H
#define __FSL_BMAN_H
/* wrapper for 48-bit buffers */
struct bm_buffer {
union {
struct {
__be16 bpid; /* hi 8-bits reserved */
__be16 hi; /* High 16-bits of 48-bit address */
__be32 lo; /* Low 32-bits of 48-bit address */
};
__be64 data;
};
} __aligned(8);
/*
* Restore the 48 bit address previously stored in BMan
* hardware pools as a dma_addr_t
*/
static inline dma_addr_t bm_buf_addr(const struct bm_buffer *buf)
{
return be64_to_cpu(buf->data) & 0xffffffffffffLLU;
}
static inline u64 bm_buffer_get64(const struct bm_buffer *buf)
{
return be64_to_cpu(buf->data) & 0xffffffffffffLLU;
}
static inline void bm_buffer_set64(struct bm_buffer *buf, u64 addr)
{
buf->hi = cpu_to_be16(upper_32_bits(addr));
buf->lo = cpu_to_be32(lower_32_bits(addr));
}
static inline u8 bm_buffer_get_bpid(const struct bm_buffer *buf)
{
return be16_to_cpu(buf->bpid) & 0xff;
}
static inline void bm_buffer_set_bpid(struct bm_buffer *buf, int bpid)
{
buf->bpid = cpu_to_be16(bpid & 0xff);
}
/* Managed portal, high-level i/face */
/* Portal and Buffer Pools */
struct bman_portal;
struct bman_pool;
#define BM_POOL_MAX 64 /* max # of buffer pools */
/**
* bman_new_pool - Allocates a Buffer Pool object
*
* Creates a pool object, and returns a reference to it or NULL on error.
*/
struct bman_pool *bman_new_pool(void);
/**
* bman_free_pool - Deallocates a Buffer Pool object
* @pool: the pool object to release
*/
void bman_free_pool(struct bman_pool *pool);
/**
* bman_get_bpid - Returns a pool object's BPID.
* @pool: the pool object
*
* The returned value is the index of the encapsulated buffer pool,
* in the range of [0, @BM_POOL_MAX-1].
*/
int bman_get_bpid(const struct bman_pool *pool);
/**
* bman_release - Release buffer(s) to the buffer pool
* @pool: the buffer pool object to release to
* @bufs: an array of buffers to release
* @num: the number of buffers in @bufs (1-8)
*
* Adds the given buffers to RCR entries. If the RCR ring is unresponsive,
* the function will return -ETIMEDOUT. Otherwise, it returns zero.
*/
int bman_release(struct bman_pool *pool, const struct bm_buffer *bufs, u8 num);
/**
* bman_acquire - Acquire buffer(s) from a buffer pool
* @pool: the buffer pool object to acquire from
* @bufs: array for storing the acquired buffers
* @num: the number of buffers desired (@bufs is at least this big)
*
* Issues an "Acquire" command via the portal's management command interface.
* The return value will be the number of buffers obtained from the pool, or a
* negative error code if a h/w error or pool starvation was encountered. In
* the latter case, the content of @bufs is undefined.
*/
int bman_acquire(struct bman_pool *pool, struct bm_buffer *bufs, u8 num);
#endif /* __FSL_BMAN_H */
ad'/>
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt()
call in intel_unpin_fb_obj() returns NULL, resulting in an oops
immediately afterwards as the (inlined) call to i915_vma_unpin_fence()
tries to dereference it.
It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server. The call chains were different:
- VT ioctl(KDSETMODE, KD_TEXT):
intel_cleanup_plane_fb+0x5b/0xa0 [i915]
drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
intel_atomic_commit_tail+0x749/0xfe0 [i915]
intel_atomic_commit+0x3cb/0x4f0 [i915]
drm_atomic_commit+0x4b/0x50 [drm]
restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
intel_fbdev_set_par+0x18/0x70 [i915]
fb_set_var+0x236/0x460
fbcon_blank+0x30f/0x350
do_unblank_screen+0xd2/0x1a0
vt_ioctl+0x507/0x12a0
tty_ioctl+0x355/0xc30
do_vfs_ioctl+0xa3/0x5e0
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x13/0x94
- i915 unpin_work workqueue:
intel_unpin_work_fn+0x58/0x140 [i915]
process_one_work+0x1f1/0x480
worker_thread+0x48/0x4d0
kthread+0x101/0x140
and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.
Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.
[ Reported it originally to the i915 developers on Jan 8, applying the
ugly workaround on my own now after triggering the problem for the
second time with no feedback.
This is likely to be the same bug reported as
https://bugs.freedesktop.org/show_bug.cgi?id=98829
https://bugs.freedesktop.org/show_bug.cgi?id=99134
which has a patch for the underlying problem, but it hasn't gotten to
me, so I'm applying the workaround. ]
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>