Re: [PATCH 6.18 000/212] 6.18.20-rc1 review

Re: [PATCH 6.18 000/212] 6.18.20-rc1 review

[Miguel Ojeda]

On Mon, 23 Mar 2026 14:43:41 +0100 Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
>
> This is the start of the stable review cycle for the 6.18.20 release.
> There are 212 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Wed, 25 Mar 2026 13:44:33 +0000.
> Anything received after that time might be too late.

Boot-tested under QEMU for Rust x86_64, arm64 and riscv64; built-tested
for loongarch64:

Tested-by: Miguel Ojeda <ojeda@kernel.org>

For UML, I am seeing:

    In file included from kernel/fork.c:108:
    In file included from ./include/linux/unwind_deferred.h:6:
    In file included from ./include/linux/unwind_user.h:6:
    ./arch/x86/include/asm/unwind_user.h:23:12: error: no member named 'flags' in 'struct pt_regs'
       23 |         if (regs->flags & X86_VM_MASK)
          |             ~~~~  ^
    ./arch/x86/include/asm/unwind_user.h:23:20: error: use of undeclared identifier 'X86_VM_MASK'
       23 |         if (regs->flags & X86_VM_MASK)
          |                           ^
    ./arch/x86/include/asm/unwind_user.h:26:7: error: call to undeclared function 'user_64bit_mode'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
       26 |         if (!user_64bit_mode(regs))
          |              ^

We probably need at least:

  aa7387e79a5c ("unwind_user/x86: Fix arch=um build")

Or perhaps the split of the guards added later.

Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>

Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-um@lists.infradead.org

I hope that helps!

Cheers,
Miguel

Re: [PATCH 6.18 000/212] 6.18.20-rc1 review

[Thorsten Leemhuis]

On 3/25/26 02:04, Miguel Ojeda wrote:
> On Mon, 23 Mar 2026 14:43:41 +0100 Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
> 
> For UML, I am seeing:

Guenter (now CCed) just reported something similar down in the thread.
And I got a similar bug report about it as well, which bisected it to
49cf34c0815f93 ("unwind_user/x86: Enable frame pointer unwinding on
x86") [v6.19-rc1, v6.18.17 (b9537a51b65af0)]:
https://bugzilla.kernel.org/show_bug.cgi?id=221283

> [...]
> 
>   aa7387e79a5c ("unwind_user/x86: Fix arch=um build")

The users in that bug reported confirmed that this fixed things:
https://bugzilla.kernel.org/show_bug.cgi?id=221283#c12

Greg, Sasha, could you pick this up please for 6.18.y?

Ciao, Thorsten

Re: [PATCH 6.18 000/212] 6.18.20-rc1 review

[Greg KH]

On Mon, Mar 30, 2026 at 07:48:50PM +0200, Thorsten Leemhuis wrote:
> On 3/25/26 02:04, Miguel Ojeda wrote:
> > On Mon, 23 Mar 2026 14:43:41 +0100 Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
> > 
> > For UML, I am seeing:
> 
> Guenter (now CCed) just reported something similar down in the thread.
> And I got a similar bug report about it as well, which bisected it to
> 49cf34c0815f93 ("unwind_user/x86: Enable frame pointer unwinding on
> x86") [v6.19-rc1, v6.18.17 (b9537a51b65af0)]:
> https://bugzilla.kernel.org/show_bug.cgi?id=221283
> 
> > [...]
> > 
> >   aa7387e79a5c ("unwind_user/x86: Fix arch=um build")
> 
> The users in that bug reported confirmed that this fixed things:
> https://bugzilla.kernel.org/show_bug.cgi?id=221283#c12
> 
> Greg, Sasha, could you pick this up please for 6.18.y?

Now added, thanks.

greg k-h