From: Felipe Contreras <[email protected]> We need to protect not only the dmm_map list, but the individual map_obj's, otherwise, we might be building the scatter-gather list with garbage. So, use the existing proc_lock for that.
I observed race conditions which caused kernel panics while running stress tests, also, Tuomas Kulve found it happening quite often in Gumstix Over. This patch fixes those. Cc: Tuomas Kulve <[email protected]> Signed-off-by: Felipe Contreras <[email protected]> Signed-off-by: Omar Ramirez Luna <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/staging/tidspbridge/rmgr/proc.c | 19 ++++++++++++++----- 1 files changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/staging/tidspbridge/rmgr/proc.c b/drivers/staging/tidspbridge/rmgr/proc.c index 54f6133..c4e5c4e 100644 --- a/drivers/staging/tidspbridge/rmgr/proc.c +++ b/drivers/staging/tidspbridge/rmgr/proc.c @@ -779,12 +779,14 @@ int proc_begin_dma(void *hprocessor, void *pmpu_addr, u32 ul_size, (u32)pmpu_addr, ul_size, dir); + mutex_lock(&proc_lock); + /* find requested memory are in cached mapping information */ map_obj = find_containing_mapping(pr_ctxt, (u32) pmpu_addr, ul_size); if (!map_obj) { pr_err("%s: find_containing_mapping failed\n", __func__); status = -EFAULT; - goto err_out; + goto no_map; } if (memory_give_ownership(map_obj, (u32) pmpu_addr, ul_size, dir)) { @@ -793,6 +795,8 @@ int proc_begin_dma(void *hprocessor, void *pmpu_addr, u32 ul_size, status = -EFAULT; } +no_map: + mutex_unlock(&proc_lock); err_out: return status; @@ -817,21 +821,24 @@ int proc_end_dma(void *hprocessor, void *pmpu_addr, u32 ul_size, (u32)pmpu_addr, ul_size, dir); + mutex_lock(&proc_lock); + /* find requested memory are in cached mapping information */ map_obj = find_containing_mapping(pr_ctxt, (u32) pmpu_addr, ul_size); if (!map_obj) { pr_err("%s: find_containing_mapping failed\n", __func__); status = -EFAULT; - goto err_out; + goto no_map; } if (memory_regain_ownership(map_obj, (u32) pmpu_addr, ul_size, dir)) { pr_err("%s: InValid address parameters %p %x\n", __func__, pmpu_addr, ul_size); status = -EFAULT; - goto err_out; } +no_map: + mutex_unlock(&proc_lock); err_out: return status; } @@ -1724,9 +1731,8 @@ int proc_un_map(void *hprocessor, void *map_addr, (p_proc_object->bridge_context, va_align, size_align); } - mutex_unlock(&proc_lock); if (status) - goto func_end; + goto unmap_failed; /* * A successful unmap should be followed by removal of map_obj @@ -1735,6 +1741,9 @@ int proc_un_map(void *hprocessor, void *map_addr, */ remove_mapping_information(pr_ctxt, (u32) map_addr, size_align); +unmap_failed: + mutex_unlock(&proc_lock); + func_end: dev_dbg(bridge, "%s: hprocessor: 0x%p map_addr: 0x%p status: 0x%x\n", __func__, hprocessor, map_addr, status); -- 1.7.4.1 _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
