4.4.301-rc1 review

This is the start of the stable review cycle for the 4.4.301 release. There are 1 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.

Responses should be made by Sat, 29 Jan 2022 18:02:51 +0000. Anything received after that time might be too late.

The whole patch series can be found in one patch at:

	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.4.301-rc1.gz

or in the git tree and branch at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.4.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <[email protected]>

    Linux 4.4.301-rc1

Tvrtko Ursulin <[email protected]>
drm/i915: Flush TLBs before releasing backing store

-------------

Diffstat:

 Makefile                            |  4 +-
 drivers/gpu/drm/i915/i915_drv.h     |  5 +++
 drivers/gpu/drm/i915/i915_gem.c     | 89 +++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_gem_gtt.c |  3 ++
 drivers/gpu/drm/i915/i915_reg.h     |  6 +++
 5 files changed, 105 insertions(+), 2 deletions(-)

From: Tvrtko Ursulin <[email protected]>

commit 7938d61591d33394a21bdd7797a245b65428f44c upstream.

We need to flush TLBs before releasing backing store otherwise userspace is able to encounter stale entries if a) it is not declaring access to certain buffers and b) it races with the backing store release from a such undeclared execution already executing on the GPU in parallel.

The approach taken is to mark any buffer objects which were ever bound to the GPU and to trigger a serialized TLB flush when their backing store is released.

Alternatively the flushing could be done on VMA unbind, at which point we would be able to ascertain whether there is potential a parallel GPU execution (which could race), but essentially it boils down to paying the cost of TLB flushes potentially needlessly at VMA unbind time (when the backing store is not known to be going away so not needed for safety), versus potentially needlessly at backing store relase time (since we at that point cannot tell whether there is anything executing on the GPU which uses that object).

Thereforce simplicity of implementation has been chosen for now with scope to benchmark and refine later as required.

---
 drivers/gpu/drm/i915/i915_drv.h     |    5 ++
 drivers/gpu/drm/i915/i915_gem.c     |   89 ++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_gem_gtt.c |    3 +
 drivers/gpu/drm/i915/i915_reg.h     |    6 ++
 4 files changed, 103 insertions(+)

@@ -1719,6 +1719,8 @@ struct drm_i915_private {
 
 	struct intel_uncore uncore;
 
+	struct mutex tlb_invalidate_lock;
+
 	struct i915_virtual_gpu vgpu;
 
 	struct intel_guc guc;

@@ -2066,6 +2068,9 @@ struct drm_i915_gem_object {
 	 */
 	unsigned int active:I915_NUM_RINGS;
 
+	unsigned long flags;
+#define I915_BO_WAS_BOUND_BIT    0
+
 	/**
 	 * This is set if the object has been written to since last bound
 	 * to the GTT

@@ -3538,6 +3538,9 @@ int i915_vma_bind(struct i915_vma *vma,
 
 	vma->bound |= bind_flags;
 
+	if (vma->obj)
+		set_bit(I915_BO_WAS_BOUND_BIT, &vma->obj->flags);
+
 	return 0;
 }
 

@@ -1592,6 +1592,12 @@ enum skl_disp_power_wells {
 
 #define GEN7_TLB_RD_ADDR	0x4700
 
+#define GEN8_RTCR	0x4260
+#define GEN8_M1TCR	0x4264
+#define GEN8_M2TCR	0x4268
+#define GEN8_BTCR	0x426c
+#define GEN8_VTCR	0x4270
+
 #if 0
 #define PRB0_TAIL	0x02030
 #define PRB0_HEAD	0x02034

Hi!

CIP testing did not find any problems here:

https://gitlab.com/cip-project/cip-testing/linux-stable-rc-ci/-/tree/linux-4.4.y

Best regards,
Pavel

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

Compiled and booted on my test system. No dmesg regressions.

thanks,
-- Shuah

All tests passing for Tegra ...

Test results for stable-v4.4:

    6 builds:	6 pass, 0 fail
    12 boots:	12 pass, 0 fail
    30 tests:	30 pass, 0 fail

Linux version: 4.4.301-rc1-g187d7c3b8ca0
Boards tested: tegra124-jetson-tk1, tegra20-ventana,

                tegra30-cardhu-a04

Jon

Build results:

	total: 160 pass: 160 fail: 0
Qemu test results:
	total: 342 pass: 342 fail: 0

Guenter

Results from Linaro’s test farm.
No regressions on arm64, arm, x86_64, and i386.

## Build
* kernel: 4.4.301-rc1
* git: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
* git branch: linux-4.4.y
* git commit: 187d7c3b8ca09131c71f6dbb8c8761f7f809402c
* git describe: v4.4.300-2-g187d7c3b8ca0
* test details:
https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-4.4.y/build/v4.4.300-2-g187d7c3b8ca0

## Test Regressions (compared to v4.4.299-114-g67ca9c44f63d) No test regressions found.

## Metric Regressions (compared to v4.4.299-114-g67ca9c44f63d) No metric regressions found.

## Test Fixes (compared to v4.4.299-114-g67ca9c44f63d) No test fixes found.

## Metric Fixes (compared to v4.4.299-114-g67ca9c44f63d) No metric fixes found.

## Test result summary
total: 33090, pass: 26341, fail: 104, skip: 5946, xfail: 699

## Build Summary
* arm: 129 total, 129 passed, 0 failed
* arm64: 31 total, 31 passed, 0 failed
* i386: 18 total, 18 passed, 0 failed
* juno-r2: 1 total, 1 passed, 0 failed
* mips: 22 total, 22 passed, 0 failed
* sparc: 12 total, 12 passed, 0 failed
* x15: 1 total, 1 passed, 0 failed
* x86: 1 total, 1 passed, 0 failed
* x86_64: 30 total, 24 passed, 6 failed

## Test suites summary
* kselftest-bpf
* kselftest-intel_pstate
* kselftest-kvm
* kselftest-livepatch
* kselftest-ptrace
* kselftest-timens
* kselftest-timers
* kselftest-tmpfs
* kselftest-tpm2
* kselftest-user
* kselftest-vm
* kselftest-zram
* libhugetlbfs
* linux-log-parser
* ltp-cap_bounds-tests
* ltp-commands-tests
* ltp-containers-tests
* ltp-controllers-tests
* ltp-cpuhotplug-tests
* ltp-crypto-tests
* ltp-cve-tests
* ltp-dio-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-math-tests
* ltp-mm-tests
* ltp-nptl-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* ltp-syscalls-tests
* ltp-tracing-tests
* network-basic-tests
* packetdrill
* perf
* v4l2-compliance

--
Linaro LKFT
https://lkft.linaro.org