[PATCH 5.15 314/917] parisc: fix warning in flush_tlb_all

Greg Kroah-Hartman
2021-11-16T01:00:10Z

From: Sven Schnelle <svens@stackframe.org>

[ Upstream commit 1030d681319b43869e0d5b568b9d0226652d1a6f ]

I've got the following splat after enabling preemption:

[ 3.724721] BUG: using __this_cpu_add() in preemptible [00000000] code: swapper/0/1
[ 3.734630] caller is __this_cpu_preempt_check+0x38/0x50
[ 3.740635] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc4-64bit+ #324
[ 3.744605] Hardware name: 9000/785/C8000
[ 3.744605] Backtrace:
[ 3.744605] [<00000000401d9d58>] show_stack+0x74/0xb0
[ 3.744605] [<0000000040c27bd4>] dump_stack_lvl+0x10c/0x188
[ 3.744605] [<0000000040c27c84>] dump_stack+0x34/0x48
[ 3.744605] [<0000000040c33438>] check_preemption_disabled+0x178/0x1b0
[ 3.744605] [<0000000040c334f8>] __this_cpu_preempt_check+0x38/0x50
[ 3.744605] [<00000000401d632c>] flush_tlb_all+0x58/0x2e0
[ 3.744605] [<00000000401075c0>] 0x401075c0
[ 3.744605] [<000000004010b8fc>] 0x4010b8fc
[ 3.744605] [<00000000401080fc>] 0x401080fc
[ 3.744605] [<00000000401d5224>] do_one_initcall+0x128/0x378
[ 3.744605] [<0000000040102de8>] 0x40102de8
[ 3.744605] [<0000000040c33864>] kernel_init+0x60/0x3a8
[ 3.744605] [<00000000401d1020>] ret_from_kernel_thread+0x20/0x28
[ 3.744605]

Fix this by moving the __inc_irq_stat() into the locked section.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/parisc/mm/init.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 3f7d6d5b56ac8..65f50f072a87b 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -842,9 +842,9 @@ void flush_tlb_all(void)
{
int do_recycle;

- __inc_irq_stat(irq_tlb_count);
do_recycle = 0;
spin_lock(&sid_lock);
+ __inc_irq_stat(irq_tlb_count);
if (dirty_space_ids > RECYCLE_THRESHOLD) {
BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */
get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
@@ -863,8 +863,8 @@ void flush_tlb_all(void)
#else
void flush_tlb_all(void)
{
- __inc_irq_stat(irq_tlb_count);
spin_lock(&sid_lock);
+ __inc_irq_stat(irq_tlb_count);
flush_tlb_all_local(NULL);
recycle_sids();
spin_unlock(&sid_lock);
--
2.33.0