On 11/20/2017 5:51 PM, Rasmus Villemoes wrote: > This reverts commit 92266d6ef60c2381c980c6cdcb2a5c1667b36b49, which > was simply wrong: In the case where domain is NULL, we now use the > wrong offsetof() in the list_first_entry macro, so we don't actually > fetch the ->cookie value, but rather the eight bytes located > sizeof(struct list_head) further into the struct async_entry. > > On 64 bit, that's the data member, while on 32 bit, we get a u64 built > from func and data in some order. > > I think the bug happens to be harmless in practice: It obviously only > affects callers which pass a NULL domain, and AFAICT the only such > caller is > > async_synchronize_full() -> > async_synchronize_full_domain(NULL) -> > async_synchronize_cookie_domain(ASYNC_COOKIE_MAX, NULL) > > and the ASYNC_COOKIE_MAX means that in practice we end up waiting for > the async_global_pending list to be empty - but it would break if > somebody happened to pass (void*)-1 as the data element to > async_schedule, and of course also if somebody ever does a > async_synchronize_cookie_domain(, NULL) with a "finite" cookie value. > > Cc: stable@xxxxxxxxxxxxxxx # 3.10+ Recommend adding "Fixes" notation here referencing the original broken commit. > Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> > --- [..] -- Adam Wallis Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.