* Re: [PATCH] arm64: Show three registers per line
2021-04-20 17:22 [PATCH] arm64: Show three registers per line Matthew Wilcox (Oracle)
@ 2021-04-20 18:57 ` Kees Cook
2021-04-21 8:31 ` David Laight
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Kees Cook @ 2021-04-20 18:57 UTC (permalink / raw)
To: Matthew Wilcox (Oracle)
Cc: Catalin Marinas, Will Deacon, Mark Rutland, Peter Zijlstra,
Marc Zyngier, Vincenzo Frascino, linux-arm-kernel, linux-kernel
On Tue, Apr 20, 2021 at 06:22:45PM +0100, Matthew Wilcox (Oracle) wrote:
> Displaying two registers per line takes 15 lines. That improves to just
> 10 lines if we display three registers per line, which reduces the amount
> of information lost when oopses are cut off. It stays within 80 columns
> and matches x86-64.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 5+ messages in thread* RE: [PATCH] arm64: Show three registers per line
2021-04-20 17:22 [PATCH] arm64: Show three registers per line Matthew Wilcox (Oracle)
2021-04-20 18:57 ` Kees Cook
@ 2021-04-21 8:31 ` David Laight
2021-04-22 10:35 ` Will Deacon
2021-04-23 17:11 ` Catalin Marinas
3 siblings, 0 replies; 5+ messages in thread
From: David Laight @ 2021-04-21 8:31 UTC (permalink / raw)
To: 'Matthew Wilcox (Oracle)',
Catalin Marinas, Will Deacon, Mark Rutland, Peter Zijlstra,
Kees Cook, Marc Zyngier, Vincenzo Frascino
Cc: linux-arm-kernel, linux-kernel
From: Matthew Wilcox
> Sent: 20 April 2021 18:23
>
> Displaying two registers per line takes 15 lines. That improves to just
> 10 lines if we display three registers per line, which reduces the amount
> of information lost when oopses are cut off. It stays within 80 columns
> and matches x86-64.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
> arch/arm64/kernel/process.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> index 6e60aa3b5ea9..aff5a2c12297 100644
> --- a/arch/arm64/kernel/process.c
> +++ b/arch/arm64/kernel/process.c
> @@ -294,13 +294,10 @@ void __show_regs(struct pt_regs *regs)
> i = top_reg;
>
> while (i >= 0) {
> - printk("x%-2d: %016llx ", i, regs->regs[i]);
> - i--;
> + printk("x%-2d: %016llx", i, regs->regs[i]);
>
> - if (i % 2 == 0) {
> - pr_cont("x%-2d: %016llx ", i, regs->regs[i]);
> - i--;
> - }
> + while (i-- % 3)
> + pr_cont(" x%-2d: %016llx", i, regs->regs[i]);
>
> pr_cont("\n");
> }
I think I'd avoid pr_cont() to avoid 'mishaps' during concurrent oops.
This probably needs something like:
for (; i >= 0; i -= 3) {
switch (i) {
case 0:
printk("x%-2d: %016llx\n", i, regs->regs[i]);
break;
case 1:
printk("x%-2d: %016llx x%-2d: %016llx\n",
i, regs->regs[i], i - 1, regs->regs[i - 1]);
break;
default:
printk("x%-2d: %016llx x%-2d: %016llx x%-2d: %016llx\n",
i, regs->regs[i], i - 1, regs->regs[i - 1],
i - 2, regs->regs[i - 2]);
continue;
}
break;
}
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] arm64: Show three registers per line
2021-04-20 17:22 [PATCH] arm64: Show three registers per line Matthew Wilcox (Oracle)
2021-04-20 18:57 ` Kees Cook
2021-04-21 8:31 ` David Laight
@ 2021-04-22 10:35 ` Will Deacon
2021-04-23 17:11 ` Catalin Marinas
3 siblings, 0 replies; 5+ messages in thread
From: Will Deacon @ 2021-04-22 10:35 UTC (permalink / raw)
To: Matthew Wilcox (Oracle)
Cc: Catalin Marinas, Mark Rutland, Peter Zijlstra, Kees Cook,
Marc Zyngier, Vincenzo Frascino, linux-arm-kernel, linux-kernel
On Tue, Apr 20, 2021 at 06:22:45PM +0100, Matthew Wilcox (Oracle) wrote:
> Displaying two registers per line takes 15 lines. That improves to just
> 10 lines if we display three registers per line, which reduces the amount
> of information lost when oopses are cut off. It stays within 80 columns
> and matches x86-64.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
> arch/arm64/kernel/process.c | 9 +++------
> 1 file changed, 3 insertions(+), 6 deletions(-)
Acked-by: Will Deacon <will@kernel.org>
Will
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] arm64: Show three registers per line
2021-04-20 17:22 [PATCH] arm64: Show three registers per line Matthew Wilcox (Oracle)
` (2 preceding siblings ...)
2021-04-22 10:35 ` Will Deacon
@ 2021-04-23 17:11 ` Catalin Marinas
3 siblings, 0 replies; 5+ messages in thread
From: Catalin Marinas @ 2021-04-23 17:11 UTC (permalink / raw)
To: Peter Zijlstra, Marc Zyngier, Mark Rutland, Vincenzo Frascino,
Kees Cook, Matthew Wilcox (Oracle),
Will Deacon
Cc: linux-kernel, linux-arm-kernel
On Tue, 20 Apr 2021 18:22:45 +0100, Matthew Wilcox (Oracle) wrote:
> Displaying two registers per line takes 15 lines. That improves to just
> 10 lines if we display three registers per line, which reduces the amount
> of information lost when oopses are cut off. It stays within 80 columns
> and matches x86-64.
Applied to arm64 (for-next/core), thanks!
[1/1] arm64: Show three registers per line
https://git.kernel.org/arm64/c/0bca3ec846d7
--
Catalin
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 5+ messages in thread