On 2018-10-19 11:22 a.m., Bart Van Assche wrote:
On Fri, 2018-10-19 at 02:24 -0400, Douglas Gilbert wrote:static void -sg_fill_request_table(struct sg_fd *sfp, struct sg_req_info *rinfo) +sg_fill_request_table(struct sg_fd *sfp, struct sg_req_info *rinfo, + int max_num) { struct sg_request *srp; int val; - unsigned int ms;val = 0;- list_for_each_entry(srp, &sfp->rq_list, entry) { - if (val >= SG_MAX_QUEUE) - break; - rinfo[val].req_state = srp->done + 1; + list_for_each_entry(srp, &sfp->rq_list, rq_entry) { + if (val >= max_num) + return;What protects the sfp->rq_list against concurrent changes? It seems to me like all other code that iterates over or modifies that list protects that list with rq_list_lock?
Bart, The function is called from sg_ioctl() case SG_GET_REQUEST_TABLE and at the call point the read_lock is held on rq_list_lock. Maybe I can add a comment above the function about the lock being held. [At least it is as the end of the patch series, and that is all I care about :-)] Doug Gilbert P.S. Best to look at sg.c after each patch is applied, not the !@#$ing stupid patches.
