Juergen Gross 90b926e68f x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case ... Since 72cbc8f04f ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen") PAT can be enabled without MTRR. This has resulted in problems e.g. for a SEV-SNP guest running under Hyper-V, when trying to establish a new mapping via memremap() with WB caching mode, as pat_x_mtrr_type() will call mtrr_type_lookup(), which in turn is returning MTRR_TYPE_INVALID due to MTRR being disabled in this configuration. The result is a mapping with UC- caching, leading to severe performance degradation. Fix that by handling MTRR_TYPE_INVALID the same way as MTRR_TYPE_WRBACK in pat_x_mtrr_type() because MTRR_TYPE_INVALID means MTRRs are disabled. [ bp: Massage commit message. ] Fixes: 72cbc8f04f ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen") Reported-by: Michael Kelley (LINUX) <mikelley@microsoft.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/20230110065427.20767-1-jgross@suse.com		2023-01-10 17:21:53 +01:00
..
cpa-test.c	treewide: use get_random_u32_below() instead of deprecated function	2022-11-18 02:15:15 +01:00
Makefile
memtype_interval.c	mm: reorder includes after introduction of linux/pgtable.h	2020-06-09 09:39:13 -07:00
memtype.c	x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case	2023-01-10 17:21:53 +01:00
memtype.h
set_memory.c	New Feature:	2022-12-17 14:06:53 -06:00