From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Thu, 5 Nov 2020 15:07:06 +0000 (+0100)
Subject: 4.19-stable patches
X-Git-Tag: v5.9.6~6
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=444d5f06ac9ddeb3b2e29122e13feb17feec52fe;p=thirdparty%2Fkernel%2Fstable-queue.git

4.19-stable patches

added patches:
	drm-i915-break-up-error-capture-compression-loops-with-cond_resched.patch
---

diff --git a/queue-4.19/drm-i915-break-up-error-capture-compression-loops-with-cond_resched.patch b/queue-4.19/drm-i915-break-up-error-capture-compression-loops-with-cond_resched.patch
new file mode 100644
index 00000000000..a4b498916b7
--- /dev/null
+++ b/queue-4.19/drm-i915-break-up-error-capture-compression-loops-with-cond_resched.patch
@@ -0,0 +1,48 @@
+From 7d5553147613b50149238ac1385c60e5c7cacb34 Mon Sep 17 00:00:00 2001
+From: Chris Wilson <chris@chris-wilson.co.uk>
+Date: Wed, 16 Sep 2020 10:00:58 +0100
+Subject: drm/i915: Break up error capture compression loops with cond_resched()
+
+From: Chris Wilson <chris@chris-wilson.co.uk>
+
+commit 7d5553147613b50149238ac1385c60e5c7cacb34 upstream.
+
+As the error capture will compress user buffers as directed to by the
+user, it can take an arbitrary amount of time and space. Break up the
+compression loops with a call to cond_resched(), that will allow other
+processes to schedule (avoiding the soft lockups) and also serve as a
+warning should we try to make this loop atomic in the future.
+
+Testcase: igt/gem_exec_capture/many-*
+Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
+Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
+Cc: stable@vger.kernel.org
+Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
+Link: https://patchwork.freedesktop.org/patch/msgid/20200916090059.3189-2-chris@chris-wilson.co.uk
+(cherry picked from commit 293f43c80c0027ff9299036c24218ac705ce584e)
+Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/gpu/drm/i915/i915_gpu_error.c |    3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/drivers/gpu/drm/i915/i915_gpu_error.c
++++ b/drivers/gpu/drm/i915/i915_gpu_error.c
+@@ -268,6 +268,8 @@ static int compress_page(struct compress
+ 
+ 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
+ 			return -EIO;
++
++		cond_resched();
+ 	} while (zstream->avail_in);
+ 
+ 	/* Fallback to uncompressed if we increase size? */
+@@ -347,6 +349,7 @@ static int compress_page(struct compress
+ 	if (!i915_memcpy_from_wc(ptr, src, PAGE_SIZE))
+ 		memcpy(ptr, src, PAGE_SIZE);
+ 	dst->pages[dst->page_count++] = ptr;
++	cond_resched();
+ 
+ 	return 0;
+ }