Re: [PATCH v3 4/6] x86/MCE: Make number of MCA banks per_cpu
From: Borislav Petkov
Date: Tue May 21 2019 - 16:31:10 EST
On Tue, May 21, 2019 at 05:52:42PM +0000, Ghannam, Yazen wrote:
> This message comes from ___might_sleep() which checks the
> On CPU0, system_state=SYSTEM_BOOTING.
> On every other CPU, system_state=SYSTEM_SCHEDULING, and that's the
> only system_state where the message is shown.
Right, the check in ___might_sleep().
> Changing GFP_KERNEL to GFP_ATOMIC seems to be a fix. Is this
> appropriate? Or do you think there's something else we could try?
* If you think that accessing memory reserves is justified and the kernel
will be stressed unless allocation succeeds, you may use ``GFP_ATOMIC``.
I don't think the MCA banks representation justifies accessing memory
Can we do instead:
-static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank *, mce_banks_array);
+static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank, mce_banks_array[MAX_NR_BANKS]);
which should be something like 9*32 = 288 bytes per CPU.
Unless you have a better idea...
ECO tip #101: Trim your mails when you reply. Srsly.