Bionic SRU request submitted:
https://lists.ubuntu.com/archives/kernel-team/2018-September/095678.html

** Description changed:

- == Comment: #0 - Michael Ranweiler <mranw...@us.ibm.com> - 2018-09-10
- 19:26:14 ==
+ == SRU Justification ==
+ Due to a recent change for powernv, now the total GPU memory is no longer
+ available. This impacts performance for any application/benchmark has a
+ large GPU memory utilization.
+ 
+ IBM is requesting mainlien commit 7acf50e4efa6 in Bionic, which reverts
+ mainline commit 4b5d62ca17a1.
+ 
+ == Fix ==
+ 7acf50e4efa6 ("Revert "powerpc/powernv: Increase memory block size to 1GB on 
radix"")
+ 
+ == Regression Potential ==
+ Low.  This is a revert that was also done upstream due to a regression.
+ Limited to powerpc.
+ 
+ == Test Case ==
+ A test kernel was built with this patch and tested by the original bug 
reporter.
+ The bug reporter states the test kernel resolved the bug.
+ 
+ 
+ 
+ 
+ 
+ == Comment: #0 - Michael Ranweiler <mranw...@us.ibm.com> - 2018-09-10 
19:26:14 ==
  
  Due to a recent change for powernv, now the total GPU memory is no
  longer available. This impacts performance for any application/benchmark
  has a large GPU memory utilization.
  
- Previous amount of memory : 16128MiB 
- Current amount of available memory : 15360MiB 
+ Previous amount of memory : 16128MiB
+ Current amount of available memory : 15360MiB
  
- From Anton, describing the recent change.: 
-    powerpc/powernv: Increase memory block size to 1GB on radix
-  
-   Memory hot unplug on PowerNV radix hosts is broken. Our memory block
-   size is 256MB but since we map the linear region with very large
-   pages, each pte we tear down maps 1GB.
-  
-   A hot unplug of one 256MB memory block results in 768MB of memory
-   getting unintentionally unmapped. At this point we are likely to oops.
-  
-   Fix this by increasing our memory block size to 1GB on PowerNV radix
-   hosts.
-  
-   Fixes: 4b5d62ca17a1 ("powerpc/mm: add radix__remove_section_mapping()")
+ From Anton, describing the recent change.:
+    powerpc/powernv: Increase memory block size to 1GB on radix
  
+   Memory hot unplug on PowerNV radix hosts is broken. Our memory block
+   size is 256MB but since we map the linear region with very large
+   pages, each pte we tear down maps 1GB.
+ 
+   A hot unplug of one 256MB memory block results in 768MB of memory
+   getting unintentionally unmapped. At this point we are likely to oops.
+ 
+   Fix this by increasing our memory block size to 1GB on PowerNV radix
+   hosts.
+ 
+   Fixes: 4b5d62ca17a1 ("powerpc/mm: add
+ radix__remove_section_mapping()")
  
  This is fixed with:
  
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7acf50e4efa6

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https://bugs.launchpad.net/bugs/1792102

Title:
  Ubuntu18.04: GPU total memory is reduced

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