From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
x86@kernel.org, Steven Rostedt <rostedt@goodmis.org>,
Brian Gerst <brgerst@gmail.com>, Juergen Gross <jgross@suse.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Arnd Bergmann <arnd@arndb.de>
Subject: Re: [patch 00/15] x86/entry: Consolidation - Part V
Date: Wed, 26 Feb 2020 11:02:56 +0100 [thread overview]
Message-ID: <20200226100256.GK14946@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20200226095319.GT18400@hirez.programming.kicks-ass.net>
On Wed, Feb 26, 2020 at 10:53:19AM +0100, Peter Zijlstra wrote:
> +SYM_CODE_START_LOCAL_NOALIGN(common_idtentry)
> + /* the return address is in the %gs stack slot */
> SAVE_ALL switch_stacks=1 skip_gs=1 unwind_espfix=1
> ENCODE_FRAME_POINTER
>
> /* fixup %gs */
> GS_TO_REG %ecx
> - movl PT_GS(%esp), %edi # get the function address
> - REG_TO_PTGS %ecx
> + pushl PT_GS(%esp) # push return address
> + REG_TO_OTGS %ecx
Aside from the obvious typo, it is also completely broken because
REG_TO_PGTS relies on the stack layout, which we just wrecked.
movl PT_GS(%esp), %edi # get the return address
REG_TO_PTGS %ecx
> SET_KERNEL_GS %ecx
>
> /* fixup orig %eax */
> @@ -1348,9 +1348,8 @@ SYM_CODE_START_LOCAL_NOALIGN(common_exception)
> movl $-1, PT_ORIG_EAX(%esp) # no syscall to restart
>
> movl %esp, %eax # pt_regs pointer
pushl %edi
> + ret
> +SYM_CODE_END(common_idtentry)
Should work, although that push+ret combo is a bit awkward.
prev parent reply other threads:[~2020-02-26 10:03 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-25 22:47 [patch 00/15] x86/entry: Consolidation - Part V Thomas Gleixner
2020-02-25 22:47 ` [patch 01/15] x86/irq: Convey vector as argument and not in ptregs Thomas Gleixner
2020-02-26 5:13 ` Andy Lutomirski
2020-02-26 5:45 ` Brian Gerst
2020-02-26 20:13 ` Thomas Gleixner
2020-02-26 21:35 ` Andy Lutomirski
2020-02-26 23:50 ` Thomas Gleixner
2020-02-26 21:54 ` Brian Gerst
2020-02-26 23:43 ` Thomas Gleixner
2020-02-27 0:04 ` Brian Gerst
2020-02-25 22:47 ` [patch 02/15] x86/entry/64: Add ability to switch to IRQ stacks in idtentry Thomas Gleixner
2020-02-25 22:47 ` [patch 03/15] x86/entry: Add IRQENTRY_IRQ macro Thomas Gleixner
2020-02-26 15:05 ` Miroslav Benes
2020-02-25 22:47 ` [patch 04/15] x86/entry: Use idtentry for interrupts Thomas Gleixner
2020-02-25 22:47 ` [patch 05/15] x86/entry: Provide IDTEnTRY_SYSVEC Thomas Gleixner
2020-02-26 6:10 ` Andy Lutomirski
2020-02-26 20:15 ` Thomas Gleixner
2020-02-25 22:47 ` [patch 06/15] x86/entry: Convert APIC interrupts to IDTENTRY_SYSVEC Thomas Gleixner
2020-02-25 22:47 ` [patch 07/15] x86/entry: Convert SMP system vectors " Thomas Gleixner
2020-02-25 22:47 ` [patch 08/15] x86/entry: Convert various system vectors Thomas Gleixner
2020-02-25 22:47 ` [patch 09/15] x86/entry: Convert KVM vectors to IDTENTRY_SYSVEC Thomas Gleixner
2020-02-26 10:54 ` Paolo Bonzini
2020-02-25 22:47 ` [patch 10/15] x86/entry: Convert various hypervisor " Thomas Gleixner
2020-02-25 22:47 ` [patch 11/15] x86/entry: Convert XEN hypercall vector " Thomas Gleixner
2020-02-25 22:47 ` [patch 12/15] x86/entry: Remove the apic/BUILD interrupt leftovers Thomas Gleixner
2020-02-25 22:47 ` [patch 13/15] x86/entry/32: Remove redundant irq disable code Thomas Gleixner
2020-02-25 22:47 ` [patch 14/15] x86/entry: Provide return_from exception() Thomas Gleixner
2020-02-25 22:47 ` [patch 15/15] x86/entry: Use return_from_exception() Thomas Gleixner
2020-02-26 9:53 ` [patch 00/15] x86/entry: Consolidation - Part V Peter Zijlstra
2020-02-26 10:02 ` Peter Zijlstra [this message]
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