On 1/19/23 2:03?PM, Salvatore Bonaccorso wrote: > Hi Luis, all, > > On Thu, Jan 19, 2023 at 10:16:34AM -0300, Luis Claudio R. Goncalves wrote: >> On Thu, Jan 19, 2023 at 12:38:25PM +0100, Pavel Machek wrote: >>> Hi! >>> >>>>> I'm pleased to announce the 5.10.162-rt78 stable release. >>>>> >>>>> You can get this release via the git tree at: >>>>> >>>>> git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git >>>>> >>>>> branch: v5.10-rt >>>>> Head SHA1: 143ef105f40a65f3ddd57121d4b4bc36eb10cc06 >>>>> >>>>> Or to build 5.10.162-rt78 directly, the following patches should be applied: >>> >>>> I see that vanilla 5.10.162-rt78 fails to build with arm64 defconfig. [0] Full log [1] >>>> Any pointers on what maybe wrong? >>> >>> We see the same failure. >>> >>>> AS arch/arm64/kernel/entry.o >>>> arch/arm64/kernel/entry.S: Assembler messages: >>>> arch/arm64/kernel/entry.S:763: Error: immediate out of range at operand 3 -- `and x2,x19,#((1<<1)|(1<<0)|(1<<2)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<13)|(1<<7))' >>>> make[2]: *** [scripts/Makefile.build:367: arch/arm64/kernel/entry.o] Error 1 >>>> make[1]: *** [scripts/Makefile.build:503: arch/arm64/kernel] Error 2 >>>> make: *** [Makefile:1837: arch/arm64] Error 2 >>> >>> The line is: >>> >>>> and x2, x19, #_TIF_WORK_MASK >> >> I believe this is related to the arch/arm64/include/asm/thread_info.h >> changes in 5.10.162-rt78, specifically: >> >> 79a9991e87fe arm64: add support for TIF_NOTIFY_SIGNAL >> 1ba44dcf789d Merge tag 'v5.10.162' into v5.10-rt >> >> The first one is the original change, coming from stable v5.10.162 and the >> second one has the merge conflict I fixed in that file due to the existence >> of TIF_NEED_RESCHED_LAZY in PREEMPT_RT. >> >> It escaped me that having TIF_NEED_RESCHED_LAZY set to 13 breaks the AND >> statement reported above. Looking at >> >> b5a5a01d8e9a arm64: uaccess: remove addr_limit_user_check() >> >> specially this note >> >> To ensure that _TIF_WORK_MASK can be used as an immediate value in an >> AND instruction (as it is in `ret_to_user`), TIF_MTE_ASYNC_FAULT is >> renumbered to keep the constituent bits of _TIF_WORK_MASK contiguous. >> >> I understand that I need to either have to renumber TIF_NEED_RESCHED_LAZY >> to 8, with the risk of breaking something else, or backport commit >> b5a5a01d8e9a in order to remove TIF_FSCHECK and then safely renumber >> TIF_NEED_RESCHED_LAZY. >> >> Guidance is welcome here :) > > Should we loop in here Jens, as having some overview of the needed > changes for io_uring rebase in the 5.10.y version? (doing so in the > mail). Huh that's funky, I built and (runtime) tested this on arm64 specifically. But I do remember some details about the first 8 bits on arm, but not arm64. I guess we need to twiddle that asm to deal with eg 16 bits, rather than attempt to backport any TIF removal patches. -- Jens Axboe
