Re: linux-next: KUnit failure after merge of the mm-nonmm-unstable tree

[Alexey Dobriyan]

On Fri, Jul 03, 2026 at 05:39:59PM +0100, Mark Brown wrote:
> On Fri, Jul 03, 2026 at 03:43:35PM +0100, Mark Brown wrote:
> > Hi all,
> > 
> > After merging the mm-nonmm-unstable tree, today's linux-next failed
> > KUnit testing like this:
> > 
> > [14:20:52] Configuring KUnit Kernel ...
> > [14:20:52] Building KUnit Kernel ...
> > Populating config with:
> > $ make ARCH=arm64 O=/tmp/next/arm64_kunit olddefconfig CROSS_COMPILE=aarch64-linux-gnu-
> > Building with:
> > $ make all compile_commands.json scripts_gdb ARCH=arm64 O=/tmp/next/arm64_kunit --jobs=192 CROSS_COMPILE=aarch64-linux-gnu-
> > [14:21:06] Starting KUnit Kernel (1/1)...
> > Running tests with:
> > $ qemu-system-aarch64 -nodefaults -m 1024 -kernel /tmp/next/arm64_kunit/arch/arm64/boot/Image.gz -append 'kunit.enable=1 console=ttyAMA0 kunit_shutdown=reboot' -no-reboot -nographic -accel kvm -accel hvf -accel tcg -serial stdio -machine virt -cpu max
> > [14:22:11] ============================================================
> > [14:22:11] =================== cmdline (8 subtests) ===================
> > [14:22:11] # cmdline_test_memparse: EXPECTATION FAILED at lib/tests/cmdline_kunit.c:249
> > [14:22:11] Expected ret == e->result, but
> > [14:22:11]     ret == -16 (0xfffffffffffffff0)
> > [14:22:11]     e->result == -1 (0xffffffffffffffff)
> > [14:22:11] when parsing '0xffffffffffffffff0'
> > [14:22:11] [FAILED] cmdline_test_memparse
> > [14:22:11]     # module: cmdline_kunit
> > [14:22:11] # cmdline: pass:7 fail:1 skip:0 total:8
> > [14:22:11] # Totals: pass:7 fail:1 skip:0 total:8
> > [14:22:11] ===================== [FAILED] cmdline =====================
> > [14:22:11] ============================================================
> > [14:22:11] Testing complete. Ran 9225 tests: passed: 9104, failed: 1, skipped: 120
> > [14:22:11] Failures: cmdline.cmdline_test_memparse
> > [14:22:11] Test results stored in /tmp/next/arm64_kunit.json
> > [14:22:11] Elapsed time: 79.318s total, 0.002s configuring, 14.632s building, 64.682s running
> > 
> > I honestly have no idea what's triggering this, nothing jumps out from
> > the commits introduced in the merge of the branch.  If I have time later
> > I'll try to bisect the issue.  I have used the tree from next-20260602
> > instead.
> 
> bisect tells me it's due to:
> 
>   e595545005616 (Revert "lib: fix _parse_integer_limit() to handle overflow")

No, it is due to

	commit 9a4580db6e9f83428813f671a79486469684069f
	lib: fix memparse() to handle overflow

memparse should be rewritten with _parse_integer().