Revision e2921f9f95f1c1355a39e54dc038ad95b6e032be authored by Linus Torvalds on 26 July 2019, 21:12:54 UTC, committed by Linus Torvalds on 26 July 2019, 21:12:54 UTC
Pull drm fixes from Daniel Vetter: "Dave seems to collect an entire streak of things happening, so again me typing pull summary. Nothing nefarious here, most of the fixes are for new stuff or things users won't see. The amd-display patches are a bit different, and very much look like they should have at least some cc: stable tags. Might be amd is a bit too comfortable with their internal tree and not enough looking at upstream. Dave&me are looking into this, in case something needs rectified with process here. Also no intel fixes pull, but intel CI is general become rather good, still I guess expect a notch more for -rc3. Summary: amdgpu: - fixes for (new in 5.3) hw support (vega20, navi) - disable RAS - lots of display fixes all over (audio, DSC, dongle, clock mgr) ttm: - fix dma_free_attrs calls to appease dma debugging msm: - fixes for dma-api, locking debug and compiler splats core: - fix cmdline mode to not apply rotation if not specified (new in 5.3) - compiler warn fix" * tag 'drm-fixes-2019-07-26' of git://anongit.freedesktop.org/drm/drm: (46 commits) drm/amd/display: Set enabled to false at start of audio disable drm/amdgpu/smu: move fan rpm query into the asic specific code drm/amd/powerplay: custom peak clock freq for navi10 drm: silence variable 'conn' set but not used drm/msm: stop abusing dma_map/unmap for cache drm/msm/dpu: Correct dpu encoder spinlock initialization drm/msm: correct NULL pointer dereference in context_init drm/amd/display: handle active dongle port type is DP++ or DP case drm/amd/display: do not read link setting if edp not connected drm/amd/display: Increase size of audios array drm/amd/display: drop ASSERT() if eDP panel is not connected drm/amd/display: Only enable audio if speaker allocation exists drm/amd/display: Fix dc_create failure handling and 666 color depths drm/amd/display: allocate 4 ddc engines for RV2 drm/amd/display: put back front end initialization sequence drm/amd/display: Wait for flip to complete drm/amd/display: Change min_h_sync_width from 8 to 4 drm/amd/display: use encoder's engine id to find matched free audio device drm/amd/display: fix DMCU hang when going into Modern Standby drm/amd/display: Disable Audio on reinitialize hardware ...
patch.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* patch.c - livepatch patching functions
*
* Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
* Copyright (C) 2014 SUSE
* Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/livepatch.h>
#include <linux/list.h>
#include <linux/ftrace.h>
#include <linux/rculist.h>
#include <linux/slab.h>
#include <linux/bug.h>
#include <linux/printk.h>
#include "core.h"
#include "patch.h"
#include "transition.h"
static LIST_HEAD(klp_ops);
struct klp_ops *klp_find_ops(void *old_func)
{
struct klp_ops *ops;
struct klp_func *func;
list_for_each_entry(ops, &klp_ops, node) {
func = list_first_entry(&ops->func_stack, struct klp_func,
stack_node);
if (func->old_func == old_func)
return ops;
}
return NULL;
}
static void notrace klp_ftrace_handler(unsigned long ip,
unsigned long parent_ip,
struct ftrace_ops *fops,
struct pt_regs *regs)
{
struct klp_ops *ops;
struct klp_func *func;
int patch_state;
ops = container_of(fops, struct klp_ops, fops);
/*
* A variant of synchronize_rcu() is used to allow patching functions
* where RCU is not watching, see klp_synchronize_transition().
*/
preempt_disable_notrace();
func = list_first_or_null_rcu(&ops->func_stack, struct klp_func,
stack_node);
/*
* func should never be NULL because preemption should be disabled here
* and unregister_ftrace_function() does the equivalent of a
* synchronize_rcu() before the func_stack removal.
*/
if (WARN_ON_ONCE(!func))
goto unlock;
/*
* In the enable path, enforce the order of the ops->func_stack and
* func->transition reads. The corresponding write barrier is in
* __klp_enable_patch().
*
* (Note that this barrier technically isn't needed in the disable
* path. In the rare case where klp_update_patch_state() runs before
* this handler, its TIF_PATCH_PENDING read and this func->transition
* read need to be ordered. But klp_update_patch_state() already
* enforces that.)
*/
smp_rmb();
if (unlikely(func->transition)) {
/*
* Enforce the order of the func->transition and
* current->patch_state reads. Otherwise we could read an
* out-of-date task state and pick the wrong function. The
* corresponding write barrier is in klp_init_transition().
*/
smp_rmb();
patch_state = current->patch_state;
WARN_ON_ONCE(patch_state == KLP_UNDEFINED);
if (patch_state == KLP_UNPATCHED) {
/*
* Use the previously patched version of the function.
* If no previous patches exist, continue with the
* original function.
*/
func = list_entry_rcu(func->stack_node.next,
struct klp_func, stack_node);
if (&func->stack_node == &ops->func_stack)
goto unlock;
}
}
/*
* NOPs are used to replace existing patches with original code.
* Do nothing! Setting pc would cause an infinite loop.
*/
if (func->nop)
goto unlock;
klp_arch_set_pc(regs, (unsigned long)func->new_func);
unlock:
preempt_enable_notrace();
}
/*
* Convert a function address into the appropriate ftrace location.
*
* Usually this is just the address of the function, but on some architectures
* it's more complicated so allow them to provide a custom behaviour.
*/
#ifndef klp_get_ftrace_location
static unsigned long klp_get_ftrace_location(unsigned long faddr)
{
return faddr;
}
#endif
static void klp_unpatch_func(struct klp_func *func)
{
struct klp_ops *ops;
if (WARN_ON(!func->patched))
return;
if (WARN_ON(!func->old_func))
return;
ops = klp_find_ops(func->old_func);
if (WARN_ON(!ops))
return;
if (list_is_singular(&ops->func_stack)) {
unsigned long ftrace_loc;
ftrace_loc =
klp_get_ftrace_location((unsigned long)func->old_func);
if (WARN_ON(!ftrace_loc))
return;
WARN_ON(unregister_ftrace_function(&ops->fops));
WARN_ON(ftrace_set_filter_ip(&ops->fops, ftrace_loc, 1, 0));
list_del_rcu(&func->stack_node);
list_del(&ops->node);
kfree(ops);
} else {
list_del_rcu(&func->stack_node);
}
func->patched = false;
}
static int klp_patch_func(struct klp_func *func)
{
struct klp_ops *ops;
int ret;
if (WARN_ON(!func->old_func))
return -EINVAL;
if (WARN_ON(func->patched))
return -EINVAL;
ops = klp_find_ops(func->old_func);
if (!ops) {
unsigned long ftrace_loc;
ftrace_loc =
klp_get_ftrace_location((unsigned long)func->old_func);
if (!ftrace_loc) {
pr_err("failed to find location for function '%s'\n",
func->old_name);
return -EINVAL;
}
ops = kzalloc(sizeof(*ops), GFP_KERNEL);
if (!ops)
return -ENOMEM;
ops->fops.func = klp_ftrace_handler;
ops->fops.flags = FTRACE_OPS_FL_SAVE_REGS |
FTRACE_OPS_FL_DYNAMIC |
FTRACE_OPS_FL_IPMODIFY;
list_add(&ops->node, &klp_ops);
INIT_LIST_HEAD(&ops->func_stack);
list_add_rcu(&func->stack_node, &ops->func_stack);
ret = ftrace_set_filter_ip(&ops->fops, ftrace_loc, 0, 0);
if (ret) {
pr_err("failed to set ftrace filter for function '%s' (%d)\n",
func->old_name, ret);
goto err;
}
ret = register_ftrace_function(&ops->fops);
if (ret) {
pr_err("failed to register ftrace handler for function '%s' (%d)\n",
func->old_name, ret);
ftrace_set_filter_ip(&ops->fops, ftrace_loc, 1, 0);
goto err;
}
} else {
list_add_rcu(&func->stack_node, &ops->func_stack);
}
func->patched = true;
return 0;
err:
list_del_rcu(&func->stack_node);
list_del(&ops->node);
kfree(ops);
return ret;
}
static void __klp_unpatch_object(struct klp_object *obj, bool nops_only)
{
struct klp_func *func;
klp_for_each_func(obj, func) {
if (nops_only && !func->nop)
continue;
if (func->patched)
klp_unpatch_func(func);
}
if (obj->dynamic || !nops_only)
obj->patched = false;
}
void klp_unpatch_object(struct klp_object *obj)
{
__klp_unpatch_object(obj, false);
}
int klp_patch_object(struct klp_object *obj)
{
struct klp_func *func;
int ret;
if (WARN_ON(obj->patched))
return -EINVAL;
klp_for_each_func(obj, func) {
ret = klp_patch_func(func);
if (ret) {
klp_unpatch_object(obj);
return ret;
}
}
obj->patched = true;
return 0;
}
static void __klp_unpatch_objects(struct klp_patch *patch, bool nops_only)
{
struct klp_object *obj;
klp_for_each_object(patch, obj)
if (obj->patched)
__klp_unpatch_object(obj, nops_only);
}
void klp_unpatch_objects(struct klp_patch *patch)
{
__klp_unpatch_objects(patch, false);
}
void klp_unpatch_objects_dynamic(struct klp_patch *patch)
{
__klp_unpatch_objects(patch, true);
}
Computing file changes ...