[PATCH 5.14 019/849] parisc: Fix set_fixmap() on PA1.x CPUs

Greg Kroah-Hartman
2021-11-15T21:22:09Z

From: Helge Deller <deller@gmx.de>

commit 6e866a462867b60841202e900f10936a0478608c upstream.

Fix a kernel crash which happens on PA1.x CPUs while initializing the
FTRACE/KPROBE breakpoints. The PTE table entries for the fixmap area
were not created correctly.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: ccfbc68d41c2 ("parisc: add set_fixmap()/clear_fixmap()")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/parisc/mm/fixmap.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

--- a/arch/parisc/mm/fixmap.c
+++ b/arch/parisc/mm/fixmap.c
@@ -20,12 +20,9 @@ void notrace set_fixmap(enum fixed_addre
pte_t *pte;

if (pmd_none(*pmd))
- pmd = pmd_alloc(NULL, pud, vaddr);
-
- pte = pte_offset_kernel(pmd, vaddr);
- if (pte_none(*pte))
pte = pte_alloc_kernel(pmd, vaddr);

+ pte = pte_offset_kernel(pmd, vaddr);
set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX));
flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
}