boot stalls when booting sparc32 images on v3.16.y/v3.18.y in qemu

[Guenter Roeck <linux@roeck-us.net>]

Hi,

I recently updated the sparc32 root file system in my testbed
with one generated with buildroot.

As a result, sparc32 images no longer boot with v3.16.y and v3.18.y.
The system starts to come up, but stalls while starting syslog.
However, v3.16 and v3.18 do boot.

I bisected v3.18.y and ended up with commit 16c193364b4 ("sparc: Harden
signal return frame checks.") as culprit; bisect results below. Reverting
this commit fixes the problem for both v3.16.y and v3.18.y.

Is it worth spending any time on this, or should I just stop testing
sparc32 boot tests with v3.16.y and v3.18.y ?

Thanks,
Guenter

---
# bad: [fa42fea0d8b49ba65b49a999331950d74827a52d] Linux 3.18.131
# good: [b2776bf7149bddd1f4161f14f79520f17fc1d71d] Linux 3.18
git bisect start 'HEAD' 'v3.18'
# bad: [6e64ac0957e06a81b22f95f3509cc39b07735d3d] usb: increase ohci watchdog delay to 275 msec
git bisect bad 6e64ac0957e06a81b22f95f3509cc39b07735d3d
# good: [3e2003cccc9fb5f73a0d251dbb595f4c6e3a08bd] USB: usbfs: allow URBs to be reaped after disconnection
git bisect good 3e2003cccc9fb5f73a0d251dbb595f4c6e3a08bd
# good: [d6a1481f7411425041271c3084f3c2e399dc6526] ASoC: wm8958: Fix enum ctl accesses in a wrong type
git bisect good d6a1481f7411425041271c3084f3c2e399dc6526
# good: [bc4b57be51fa419cd870398624c763b7afb91154] Btrfs: make btrfs_abort_transaction consider existence of new block groups
git bisect good bc4b57be51fa419cd870398624c763b7afb91154
# bad: [b4d9416d6388fb450b397484e0ab85a154471723] of: fix memory leak related to safe_name()
git bisect bad b4d9416d6388fb450b397484e0ab85a154471723
# good: [35807de76e1c2b7d15eea2f947983fcd043a2db0] clk: rockchip: free memory in error cases when registering clock branches
git bisect good 35807de76e1c2b7d15eea2f947983fcd043a2db0
# bad: [cae1c6c281d8728e98f7e7a8950d6e64746b5bbc] netfilter: arp_tables: simplify translate_compat_table args
git bisect bad cae1c6c281d8728e98f7e7a8950d6e64746b5bbc
# good: [f02212dd4bd88826afccc36146177589eccb699b] tty: vt, return error when con_startup fails
git bisect good f02212dd4bd88826afccc36146177589eccb699b
# bad: [16c193364b4d6ff58c38c209e1e2b5c6fd674123] sparc: Harden signal return frame checks.
git bisect bad 16c193364b4d6ff58c38c209e1e2b5c6fd674123
# good: [09600dd82044bf676e875d3bd9c904193c31c1f0] sfc: on MC reset, clear PIO buffer linkage in TXQs
git bisect good 09600dd82044bf676e875d3bd9c904193c31c1f0
# good: [0396a871c4e3fbbaabb4f2632c1d388a04b68c84] sparc64: Fix numa node distance initialization
git bisect good 0396a871c4e3fbbaabb4f2632c1d388a04b68c84
# good: [2a3e4b3cbee2c53c53e82b6f593160fb6583b24e] sparc/PCI: Fix for panic while enabling SR-IOV
git bisect good 2a3e4b3cbee2c53c53e82b6f593160fb6583b24e
# good: [705de0f20b1751f5816952486589543aaaa0bcbe] sparc64: Take ctx_alloc_lock properly in hugetlb_setup().
git bisect good 705de0f20b1751f5816952486589543aaaa0bcbe
# first bad commit: [16c193364b4d6ff58c38c209e1e2b5c6fd674123] sparc: Harden signal return frame checks.