Messages in this thread | | | Subject | Re: lost interrupts when running sabrelite images (v4.15+) in qemu | From | Guenter Roeck <> | Date | Tue, 6 Mar 2018 06:25:15 -0800 |
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On 03/05/2018 09:30 AM, Troy Kisky wrote: > On 3/3/2018 1:12 PM, Guenter Roeck wrote: >> On 03/03/2018 12:48 PM, Guenter Roeck wrote: >>> On 03/03/2018 11:07 AM, Troy Kisky wrote: >>>> On 3/3/2018 8:32 AM, Guenter Roeck wrote: >>>>> Hi, >>>>> >>>>> since v4.15, I get the following runtime warning when running sabrelite images >>>>> in qemu. >>>>> >>>>> irq 65: nobody cared (try booting with the "irqpoll" option) >>>>> ... >>>>> handlers: >>>>> [<26292474>] fec_pps_interrupt >>>>> Disabling IRQ #65 >>>>> fec 2188000.ethernet (unnamed net_device) (uninitialized): MDIO read timeout >>>>> >>>>> Bisect points to commit 4ad1ceec05e491 ("net: fec: Let fec_ptp have its >>>>> own interrupt routine"). Analysis shows that platform_irq_count() >>>>> returns 2, which is reduced to 1 by fec_enet_get_irq_cnt(). >>>>> If I let fec_enet_get_irq_cnt() return 2, the problem is gone. >>>>> Reverting commit 4ad1ceec05e491 also fixes the problem. >>>>> >>>>> Bisect log is attached. >>>>> >>>> >>>> Sounds like you found a bug with qemu. I just booted sabrelite over nfs fine. >>>> My interrupts look like this. >>>> >>>> >>>> 64: 98767 0 0 0 GIC-0 150 Level 2188000.ethernet >>>> 65: 0 0 0 0 GIC-0 151 Level 2188000.ethernet >>>> ___________ >>>> Irq 65 is only for ptp interrrupts now. If qemu is signaling an tx/rx frame interrupt on 65, >>>> then qemu is wrong. Of course, I've never used qemu so feel free to ignore me if I make no sense. >>>> >>> >>> Thanks for checking with real hardware. >>> >>> This is what I see (with your patch reverted): >>> >>> 64: 0 GIC-0 150 Level 2188000.ethernet >>> 65: 64 GIC-0 151 Level 2188000.ethernet >>> >>> Looking into the qemu source, I see: >>> >>> #define FSL_IMX6_ENET_MAC_1588_IRQ 118 >>> #define FSL_IMX6_ENET_MAC_IRQ 119 >>> >>> FSL_IMX6_ENET_MAC_IRQ is then connected to fec interrupt index 0, and FSL_IMX6_ENET_MAC_1588_IRQ >>> is connected to fec interrupt index 1. >>> >>> This may suggest that the defines are reversed. I'll see what happens if I swap them. >>> >> >> Confirmed. If I swap the above defines, everything works fine. At the same time, >> the modified qemu works with older kernels. >> >> Thanks a lot for the hint, and sorry for the noise. >> >> Guenter >> > It definitely was not noise. I bet it helps people searching the mailing list in the future. > Thanks for posting the resolution. >
Turns out "works" as I stated above is not entirely accurate.
- v4.13 and later work - In v4.12 and earlier, the Ethernet interface fails to instantiate with fec 2188000.ethernet (unnamed net_device) (uninitialized): MDIO read timeout fec: probe of 2188000.ethernet failed with error -5 I have not found the reason yet. Unmodified qemu works fine. - v4.1 and earlier crash. The crash is fixed by commit 32cba57ba74be ("net: fec: introduce fec_ptp_stop and use in probe fail path")
There is also a matching bug at lauchpad:
https://bugs.launchpad.net/qemu/+bug/1753309
Guenter
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