Hi Hugh,
On 5/10/23 06:52, Hugh Dickins wrote:
To keep balance in future, remember to pte_unmap() after a successful
get_ptep(). And (we might as well) pretend that flush_cache_pages()
really needed a map there, to read the pfn before "unmapping".
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
---
arch/parisc/kernel/cache.c | 26 +++++++++++++++++++++-----
1 file changed, 21 insertions(+), 5 deletions(-)
diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 1d3b8bc8a623..b0c969b3a300 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -425,10 +425,15 @@ void flush_dcache_page(struct page *page)
offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
addr = mpnt->vm_start + offset;
if (parisc_requires_coherency()) {
+ bool needs_flush = false;
pte_t *ptep;
ptep = get_ptep(mpnt->vm_mm, addr);
- if (ptep && pte_needs_flush(*ptep))
+ if (ptep) {
+ needs_flush = pte_needs_flush(*ptep);
+ pte_unmap(ptep);
+ }
+ if (needs_flush)
flush_user_cache_page(mpnt, addr);
} else {
/*
@@ -560,14 +565,20 @@ EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
static void flush_cache_page_if_present(struct vm_area_struct *vma,
unsigned long vmaddr, unsigned long pfn)
{
- pte_t *ptep = get_ptep(vma->vm_mm, vmaddr);
+ bool needs_flush = false;
+ pte_t *ptep;
/*
* The pte check is racy and sometimes the flush will trigger
* a non-access TLB miss. Hopefully, the page has already been
* flushed.
*/
- if (ptep && pte_needs_flush(*ptep))
+ ptep = get_ptep(vma->vm_mm, vmaddr);
+ if (ptep) {
+ needs_flush = pte_needs_flush(*ptep))
^^^^^
One ")" too much and lacks a trailing ";"
Should be:
needs_flush = pte_needs_flush(*ptep);
With that fixed the kernel compiles and boots sucessfully on parisc.
Helge
