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authorJohn Crispin <john@phrozen.org>2016-12-25 20:11:34 +0100
committerJohn Crispin <john@phrozen.org>2017-08-05 08:46:36 +0200
commit74d00a8c3849c1340efd713eb94b786e304c201f (patch)
treede481743de61c34da96ab5f9dba3af3edcfb8260 /target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch
parentde350550ef648d9728351b986b0516fa29465c45 (diff)
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kernel: split patches folder up into backport, pending and hack folders
* properly format/comment all patches * merge debloat patches * merge Kconfig patches * merge swconfig patches * merge hotplug patches * drop 200-fix_localversion.patch - upstream * drop 222-arm_zimage_none.patch - unused * drop 252-mv_cesa_depends.patch - no longer required * drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused * drop 661-fq_codel_keep_dropped_stats.patch - outdated * drop 702-phy_add_aneg_done_function.patch - upstream * drop 840-rtc7301.patch - unused * drop 841-rtc_pt7c4338.patch - upstream * drop 921-use_preinit_as_init.patch - unused * drop spio-gpio-old and gpio-mmc - unused Signed-off-by: John Crispin <john@phrozen.org>
Diffstat (limited to 'target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch')
-rw-r--r--target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch31
1 files changed, 31 insertions, 0 deletions
diff --git a/target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch b/target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch
new file mode 100644
index 0000000000..e4ac2cd583
--- /dev/null
+++ b/target/linux/generic/pending-4.4/101-MIPS-fix-cache-flushing-for-highmem-pages.patch
@@ -0,0 +1,31 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sun, 24 Jan 2016 01:03:51 +0100
+Subject: [PATCH] MIPS: fix cache flushing for highmem pages
+
+Most cache flush ops were no-op for highmem pages. This led to nasty
+segfaults and (in the case of page_address(page) == NULL) kernel
+crashes.
+
+Fix this by always flushing highmem pages using kmap/kunmap_atomic
+around the actual cache flush. This might be a bit inefficient, but at
+least it's stable.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/arch/mips/mm/cache.c
++++ b/arch/mips/mm/cache.c
+@@ -111,6 +111,13 @@ void __flush_anon_page(struct page *page
+ {
+ unsigned long addr = (unsigned long) page_address(page);
+
++ if (PageHighMem(page)) {
++ addr = (unsigned long)kmap_atomic(page);
++ flush_data_cache_page(addr);
++ __kunmap_atomic((void *)addr);
++ return;
++ }
++
+ if (pages_do_alias(addr, vmaddr)) {
+ if (page_mapped(page) && !Page_dcache_dirty(page)) {
+ void *kaddr;