From: Nicholas Piggin npiggin@gmail.com
[ Upstream commit b4bda59b47879cce38a6ec5a01cd3cac702b5331 ]
The refcount on mm is dropped before the coprocessor is detached.
Reported-by: Sachin Sant sachinp@linux.ibm.com Fixes: 7bc6f71bdff5f ("powerpc/vas: Define and use common vas_window struct") Fixes: b22f2d88e435c ("powerpc/pseries/vas: Integrate API with open/close windows") Signed-off-by: Nicholas Piggin npiggin@gmail.com Tested-by: Sachin Sant sachinp@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/20230607101024.14559-1-npiggin@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/platforms/powernv/vas-window.c | 2 +- arch/powerpc/platforms/pseries/vas.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index 0072682531d80..b664838008c12 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -1310,8 +1310,8 @@ int vas_win_close(struct vas_window *vwin) /* if send window, drop reference to matching receive window */ if (window->tx_win) { if (window->user_win) { - put_vas_user_win_ref(&vwin->task_ref); mm_context_remove_vas_window(vwin->task_ref.mm); + put_vas_user_win_ref(&vwin->task_ref); } put_rx_win(window->rxwin); } diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c index 15046d80f0427..b54f6fc27896f 100644 --- a/arch/powerpc/platforms/pseries/vas.c +++ b/arch/powerpc/platforms/pseries/vas.c @@ -441,8 +441,8 @@ static int vas_deallocate_window(struct vas_window *vwin) atomic_dec(&caps->used_lpar_creds); mutex_unlock(&vas_pseries_mutex);
- put_vas_user_win_ref(&vwin->task_ref); mm_context_remove_vas_window(vwin->task_ref.mm); + put_vas_user_win_ref(&vwin->task_ref);
kfree(win); return 0;