This is a note to let you know that I've just added the patch titled
x86/mm: Fix __swp_entry_to_pte() for Xen PV guests
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-mm-fix-__swp_entry_to_pte-for-xen-pv-guests.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit eb0e05c8655a0d8415aefc182c3b2c57ec468938
Author: Juergen Gross <jgross@xxxxxxxx>
Date: Mon Mar 6 13:32:59 2023 +0100
x86/mm: Fix __swp_entry_to_pte() for Xen PV guests
[ Upstream commit 0f88130e8a6fd185b0aeb5d8e286083735f2585a ]
Normally __swp_entry_to_pte() is never called with a value translating
to a valid PTE. The only known exception is pte_swap_tests(), resulting
in a WARN splat in Xen PV guests, as __pte_to_swp_entry() did
translate the PFN of the valid PTE to a guest local PFN, while
__swp_entry_to_pte() doesn't do the opposite translation.
Fix that by using __pte() in __swp_entry_to_pte() instead of open
coding the native variant of it.
For correctness do the similar conversion for __swp_entry_to_pmd().
Fixes: 05289402d717 ("mm/debug_vm_pgtable: add tests validating arch helpers for core MM features")
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230306123259.12461-1-jgross@xxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 56d0399a0cd16..dd520b44e89cc 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -235,8 +235,8 @@ static inline void native_pgd_clear(pgd_t *pgd)
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val((pte)) })
#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val((pmd)) })
-#define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val })
-#define __swp_entry_to_pmd(x) ((pmd_t) { .pmd = (x).val })
+#define __swp_entry_to_pte(x) (__pte((x).val))
+#define __swp_entry_to_pmd(x) (__pmd((x).val))
extern int kern_addr_valid(unsigned long addr);
extern void cleanup_highmap(void);
