From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
Andrew Cooper <andrew.cooper3@citrix.com>,
Juergen Gross <jgross@suse.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Kees Cook <keescook@chromium.org>
Subject: Re: [RFC 12/17] x86/xen/64: Clean up SP code in cpu_initialize_context()
Date: Tue, 12 Sep 2017 15:09:52 -0500 [thread overview]
Message-ID: <20170912200952.2r7xxgtbjwl7jp6j@treble> (raw)
In-Reply-To: <b912dc9d811381af3d1476d5047e645027f8e756.1504733277.git.luto@kernel.org>
On Wed, Sep 06, 2017 at 02:36:57PM -0700, Andy Lutomirski wrote:
> @@ -293,12 +294,19 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
> #endif
> memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
>
> + /*
> + * Bring up the CPU in cpu_bringup_and_idle() with the stack
> + * pointing just below where pt_regs would be if it were a normal
> + * kernel entry.
> + */
> ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
> ctxt->flags = VGCF_IN_KERNEL;
> ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
> ctxt->user_regs.ds = __USER_DS;
> ctxt->user_regs.es = __USER_DS;
> ctxt->user_regs.ss = __KERNEL_DS;
> + ctxt->user_regs.cs = __KERNEL_CS;
> + ctxt->user_regs.esp = task_top_of_stack(idle) - sizeof(struct pt_regs);
Isn't this the same as task_pt_regs(idle)?
--
Josh
next prev parent reply other threads:[~2017-09-12 20:09 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-06 21:36 [RFC 00/17] Pile o' entry stack changes Andy Lutomirski
2017-09-06 21:36 ` [RFC 01/17] x86/asm/64: Remove the restore_c_regs_and_iret label Andy Lutomirski
2017-09-07 9:40 ` Borislav Petkov
2017-09-07 9:46 ` Ingo Molnar
2017-09-07 9:49 ` Ingo Molnar
2017-09-07 9:57 ` Borislav Petkov
2017-09-07 10:29 ` Ingo Molnar
2017-09-06 21:36 ` [RFC 02/17] x86/asm/64: Split the iret-to-user and iret-to-kernel paths Andy Lutomirski
2017-09-06 21:36 ` [RFC 03/17] x86/asm/64: Move SWAPGS into the common iret-to-usermode path Andy Lutomirski
2017-09-06 21:36 ` [RFC 04/17] x86/asm/64: Simplify reg restore code in the standard IRET paths Andy Lutomirski
2017-09-12 20:05 ` Josh Poimboeuf
2017-09-06 21:36 ` [RFC 05/17] x86/asm/64: Shrink paranoid_exit_restore and make labels local Andy Lutomirski
2017-09-06 21:36 ` [RFC 06/17] x86/asm/64: Use pop instead of movq in syscall_return_via_sysret Andy Lutomirski
2017-09-06 21:36 ` [RFC 07/17] x86/asm/64: Merge the fast and slow SYSRET paths Andy Lutomirski
2017-09-06 21:36 ` [RFC 08/17] x86/asm/64: De-Xen-ify our NMI code Andy Lutomirski
2017-09-07 9:34 ` Juergen Gross
2017-09-07 18:38 ` Andy Lutomirski
2017-09-08 4:26 ` Juergen Gross
2017-09-06 21:36 ` [RFC 09/17] x86/asm/32: Pull MSR_IA32_SYSENTER_CS update code out of native_load_sp0() Andy Lutomirski
2017-09-12 20:06 ` Josh Poimboeuf
2017-09-06 21:36 ` [RFC 10/17] x86/asm/64: Pass sp0 directly to load_sp0() Andy Lutomirski
2017-09-06 21:36 ` [RFC 11/17] x86/asm: Add task_top_of_stack() to find the top of a task's stack Andy Lutomirski
2017-09-06 21:36 ` [RFC 12/17] x86/xen/64: Clean up SP code in cpu_initialize_context() Andy Lutomirski
2017-09-12 20:09 ` Josh Poimboeuf [this message]
2017-09-06 21:36 ` [RFC 13/17] x86/boot/64: Stop initializing TSS.sp0 at boot Andy Lutomirski
2017-09-06 21:36 ` [RFC 14/17] x86/asm/64: Remove all remaining direct thread_struct::sp0 reads Andy Lutomirski
2017-09-06 21:37 ` [RFC 15/17] x86/boot/32: Fix cpu_current_top_of_stack initialization at boot Andy Lutomirski
2017-09-06 21:37 ` [RFC 16/17] x86/asm/64: Remove thread_struct::sp0 Andy Lutomirski
2017-09-06 21:37 ` [RFC 17/17] x86/traps: Use a new on_thread_stack() helper to clean up an assertion Andy Lutomirski
2017-09-12 20:11 ` Josh Poimboeuf
2017-09-12 20:25 ` Andrew Cooper
2017-09-06 22:16 ` [RFC 00/17] Pile o' entry stack changes Andi Kleen
2017-09-07 0:01 ` Andy Lutomirski
2017-09-07 7:04 ` Ingo Molnar
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