diff options
Diffstat (limited to 'debian/patches-rt/0062-highmem-Don-t-disable-preemption-on-RT-in-kmap_atomi.patch')
| -rw-r--r-- | debian/patches-rt/0062-highmem-Don-t-disable-preemption-on-RT-in-kmap_atomi.patch | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/debian/patches-rt/0062-highmem-Don-t-disable-preemption-on-RT-in-kmap_atomi.patch b/debian/patches-rt/0062-highmem-Don-t-disable-preemption-on-RT-in-kmap_atomi.patch new file mode 100644 index 000000000..cecb34498 --- /dev/null +++ b/debian/patches-rt/0062-highmem-Don-t-disable-preemption-on-RT-in-kmap_atomi.patch @@ -0,0 +1,71 @@ +From 09d7bcb6eee1e7c9351535a20f60929daca8632d Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Fri, 30 Oct 2020 13:59:06 +0100 +Subject: [PATCH 062/323] highmem: Don't disable preemption on RT in + kmap_atomic() +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.204-rt100.tar.xz + +Disabling preemption makes it impossible to acquire sleeping locks within +kmap_atomic() section. +For PREEMPT_RT it is sufficient to disable migration. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + include/linux/highmem-internal.h | 20 ++++++++++++++++---- + 1 file changed, 16 insertions(+), 4 deletions(-) + +diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h +index bd15bf9164c2..f9bc6acd3679 100644 +--- a/include/linux/highmem-internal.h ++++ b/include/linux/highmem-internal.h +@@ -90,7 +90,10 @@ static inline void __kunmap_local(void *vaddr) + + static inline void *kmap_atomic(struct page *page) + { +- preempt_disable(); ++ if (IS_ENABLED(CONFIG_PREEMPT_RT)) ++ migrate_disable(); ++ else ++ preempt_disable(); + pagefault_disable(); + return __kmap_local_page_prot(page, kmap_prot); + } +@@ -99,7 +102,10 @@ static inline void __kunmap_atomic(void *addr) + { + kunmap_local_indexed(addr); + pagefault_enable(); +- preempt_enable(); ++ if (IS_ENABLED(CONFIG_PREEMPT_RT)) ++ migrate_enable(); ++ else ++ preempt_enable(); + } + + unsigned int __nr_free_highpages(void); +@@ -172,7 +178,10 @@ static inline void __kunmap_local(void *addr) + + static inline void *kmap_atomic(struct page *page) + { +- preempt_disable(); ++ if (IS_ENABLED(CONFIG_PREEMPT_RT)) ++ migrate_disable(); ++ else ++ preempt_disable(); + pagefault_disable(); + return page_address(page); + } +@@ -183,7 +192,10 @@ static inline void __kunmap_atomic(void *addr) + kunmap_flush_on_unmap(addr); + #endif + pagefault_enable(); +- preempt_enable(); ++ if (IS_ENABLED(CONFIG_PREEMPT_RT)) ++ migrate_enable(); ++ else ++ preempt_enable(); + } + + static inline unsigned int nr_free_highpages(void) { return 0; } +-- +2.43.0 + |