Re: [PATCH net] net: dsa: qca8k: Fix "Unexpected gfp" kernel exception

[Andrew Lunn]

On Wed, Jun 03, 2020 at 01:31:39PM +0200, Michal VokÃÄ wrote:
> Commit 7e99e3470172 ("net: dsa: remove dsa_switch_alloc helper")
> replaced the dsa_switch_alloc helper by devm_kzalloc in all DSA
> drivers. Unfortunately it introduced a typo in qca8k.c driver and
> wrong argument is passed to the devm_kzalloc function.
> 
> This fix mitigates the following kernel exception:
> 
>   Unexpected gfp: 0x6 (__GFP_HIGHMEM|GFP_DMA32). Fixing up to gfp: 0x101 (GFP_DMA|__GFP_ZERO). Fix your code!
>   CPU: 1 PID: 44 Comm: kworker/1:1 Not tainted 5.5.9-yocto-ua #1
>   Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
>   Workqueue: events deferred_probe_work_func
>   [<c0014924>] (unwind_backtrace) from [<c00123bc>] (show_stack+0x10/0x14)
>   [<c00123bc>] (show_stack) from [<c04c8fb4>] (dump_stack+0x90/0xa4)
>   [<c04c8fb4>] (dump_stack) from [<c00e1b10>] (new_slab+0x20c/0x214)
>   [<c00e1b10>] (new_slab) from [<c00e1cd0>] (___slab_alloc.constprop.0+0x1b8/0x540)
>   [<c00e1cd0>] (___slab_alloc.constprop.0) from [<c00e2074>] (__slab_alloc.constprop.0+0x1c/0x24)
>   [<c00e2074>] (__slab_alloc.constprop.0) from [<c00e4538>] (__kmalloc_track_caller+0x1b0/0x298)
>   [<c00e4538>] (__kmalloc_track_caller) from [<c02cccac>] (devm_kmalloc+0x24/0x70)
>   [<c02cccac>] (devm_kmalloc) from [<c030d888>] (qca8k_sw_probe+0x94/0x1ac)
>   [<c030d888>] (qca8k_sw_probe) from [<c0304788>] (mdio_probe+0x30/0x54)
>   [<c0304788>] (mdio_probe) from [<c02c93bc>] (really_probe+0x1e0/0x348)
>   [<c02c93bc>] (really_probe) from [<c02c9884>] (driver_probe_device+0x60/0x16c)
>   [<c02c9884>] (driver_probe_device) from [<c02c7fb0>] (bus_for_each_drv+0x70/0x94)
>   [<c02c7fb0>] (bus_for_each_drv) from [<c02c9708>] (__device_attach+0xb4/0x11c)
>   [<c02c9708>] (__device_attach) from [<c02c8148>] (bus_probe_device+0x84/0x8c)
>   [<c02c8148>] (bus_probe_device) from [<c02c8cec>] (deferred_probe_work_func+0x64/0x90)
>   [<c02c8cec>] (deferred_probe_work_func) from [<c0033c14>] (process_one_work+0x1d4/0x41c)
>   [<c0033c14>] (process_one_work) from [<c00340a4>] (worker_thread+0x248/0x528)
>   [<c00340a4>] (worker_thread) from [<c0039148>] (kthread+0x124/0x150)
>   [<c0039148>] (kthread) from [<c00090d8>] (ret_from_fork+0x14/0x3c)
>   Exception stack(0xee1b5fb0 to 0xee1b5ff8)
>   5fa0:                                     00000000 00000000 00000000 00000000
>   5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>   5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>   qca8k 2188000.ethernet-1:0a: Using legacy PHYLIB callbacks. Please migrate to PHYLINK!
>   qca8k 2188000.ethernet-1:0a eth2 (uninitialized): PHY [2188000.ethernet-1:01] driver [Generic PHY]
>   qca8k 2188000.ethernet-1:0a eth1 (uninitialized): PHY [2188000.ethernet-1:02] driver [Generic PHY]
> 
> Fixes: 7e99e3470172 ("net: dsa: remove dsa_switch_alloc helper")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Michal VokÃÄ <michal.vokac@xxxxxxxxx>

Signed-off-by: Andrew Lunn <andrew@xxxxxxx>

    Andrew