Re: linux-next: Fixes tag needs some work in the tip tree

From: Bandan Das
Date: Thu Aug 29 2019 - 04:26:38 EST

Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> writes:

> Hi all,
> In commit
> bae3a8d3308e ("x86/apic: Do not initialize LDR and DFR for bigsmp")
> Fixes tag
> Fixes: db7b9e9f26b8 ("[PATCH] Clustered APIC setup for >8 CPU systems")
> has these problem(s):
> - Target SHA1 does not exist

I tried to dig this up and I believe that this is from pre-git.
I went back as far as commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx>
Date: Sat Apr 16 15:20:36 2005 -0700


Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

which adds init_apic_ldr() in include/asm-i386/mach-bigsmp/mach_apic.h with
the following:

+static inline void init_apic_ldr(void)
+ unsigned long val;
+ apic_write_around(APIC_DFR, APIC_DFR_VALUE);
+ val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
+ val = calculate_ldr(val);
+ apic_write_around(APIC_LDR, val);

So, the bug seems to be present here as well...


> I could not quickly find an obvious match.