On 06/11/2023 21:58, Zhu Yanjun wrote: > 在 2023/11/6 12:07, Zhijian Li (Fujitsu) 写道: >> >> >> On 03/11/2023 21:00, Zhu Yanjun wrote: >>> 在 2023/11/3 17:55, Li Zhijian 写道: >>>> I don't collect the Reviewed-by to the patch1-2 this time, since i >>>> think we can make it better. >>>> >>>> Patch1-2: Fix kernel panic[1] and benifit to make srp work again. >>>> Almost nothing change from V1. >>>> Patch3-5: cleanups # newly add >>>> Patch6: make RXE support PAGE_SIZE aligned mr # newly add, but not fully tested >>>> >>>> My bad arm64 mechine offten hangs when doing blktests even though i use the >>>> default siw driver. >>>> >>>> - nvme and ULPs(rtrs, iser) always registers 4K mr still don't supported yet. >>> >>> Zhijian >>> >>> Please read carefully the whole discussion about this problem. You will find a lot of valuable suggestions, especially suggestions from Jason. >> >> Okay, i will read it again. If you can tell me which thread, that would be better. >> >> >>> >>> From the whole discussion, it seems that the root cause is very clear. >>> We need to fix this prolem. Please do not send this kind of commits again. >>> >> >> Let's think about what's our goal first. >> >> - 1) Fix the panic[1] and only support PAGE_SIZE MR >> - 2) support PAGE_SIZE aligned MR >> - 3) support any page_size MR. >> >> I'm sorry i'm not familiar with the linux MM subsystem. It seem it's safe/correct to access >> address/memory across pages start from the return of kmap_loca_page(page). >> In other words, 2) is already native supported, right? > > Yes. Please read the comments from Jason, Leon and Bart. They shared a lot of good advice. I read the whole discussion again, but I believed i still missed a lost. > From them, we can know the root cause and how to fix this problem. I don't think i misunderstood the root cause: RXE splits memory into PAGE_SIZE units in the xarray. As a result, when we extract an address from the xarray, we should not access address beyond a PAGE_SIZE window. IIUC, then how to fix it? - I'm not going to "removing page_size set", it's out of this patch scope. Feel free to do the cleanup separately. - I'm not going to fix the NVMe/rtrs etc problems in this patch set when 64K page is enabled. But RXE will tell its callers explicitly "RXE don't don't support such page_size" - I didn't state RXE supports PAGE_SIZE aligned page_size MR before refactoring rxe_map_mr_sg(), because I worry about it was not correct to access address beyond the PAGE_SIZE window. What I should do next? Just state "RXE support PAGE_SIZE aligned MR" ? Then patches become RDMA/rxe: RDMA/rxe: don't allow registering !PAGE_SIZE aligned MR RDMA/rxe: set RXE_PAGE_SIZE_CAP to starting from PAGE_SIZE Or just keep we have done in the V1 Thanks > > Good Luck. > > Zhu Yanjun > >> >> I get totally confused now. >> >> >> >>> Zhu Yanjun >>> >>>> >>>> [1] https://lore.kernel.org/all/CAHj4cs9XRqE25jyVw9rj9YugffLn5+f=1znaBEnu1usLOciD+g@xxxxxxxxxxxxxx/T/ >>>> >>>> Li Zhijian (6): >>>> RDMA/rxe: RDMA/rxe: don't allow registering !PAGE_SIZE mr >>>> RDMA/rxe: set RXE_PAGE_SIZE_CAP to PAGE_SIZE >>>> RDMA/rxe: remove unused rxe_mr.page_shift >>>> RDMA/rxe: Use PAGE_SIZE and PAGE_SHIFT to extract address from >>>> page_list >>>> RDMA/rxe: cleanup rxe_mr.{page_size,page_shift} >>>> RDMA/rxe: Support PAGE_SIZE aligned MR >>>> >>>> drivers/infiniband/sw/rxe/rxe_mr.c | 80 ++++++++++++++++----------- >>>> drivers/infiniband/sw/rxe/rxe_param.h | 2 +- >>>> drivers/infiniband/sw/rxe/rxe_verbs.h | 9 --- >>>> 3 files changed, 48 insertions(+), 43 deletions(-) >>>> >
