| Message ID | 20230410081438.1750-3-xin3.li@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: enable FRED for x86-64 | expand |
On Mon, Apr 10, 2023 at 01:14:07AM -0700, Xin Li wrote: > diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h > index f4db78b09c8f..2abb23e6c1e2 100644 > --- a/arch/x86/include/asm/ptrace.h > +++ b/arch/x86/include/asm/ptrace.h > @@ -82,12 +82,40 @@ struct pt_regs { > * On hw interrupt, it's IRQ number: > */ > unsigned long orig_ax; > -/* Return frame for iretq */ > +/* Return frame for iretq/eretu/erets */ > unsigned long ip; > - unsigned long cs; > + union { > + unsigned long csx; /* cs extended: CS + any fields above it */ > + struct __attribute__((__packed__)) { diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 2abb23e6c1e2..d850d3072263 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -86,7 +86,7 @@ struct pt_regs { unsigned long ip; union { unsigned long csx; /* cs extended: CS + any fields above it */ - struct __attribute__((__packed__)) { + struct { unsigned short cs; /* CS selector proper */ unsigned int current_stack_level: 2; unsigned int __csx_resv1 : 6; @@ -96,13 +96,13 @@ struct pt_regs { unsigned int nmi : 1; unsigned int __csx_resv3 : 3; unsigned int __csx_resv4 : 32; - }; + } __packed; }; unsigned long flags; unsigned long sp; union { unsigned long ssx; /* ss extended: SS + any fields above it */ - struct __attribute__((__packed__)) { + struct { unsigned short ss; /* SS selector proper */ unsigned int __ssx_resv1 : 16; unsigned int vector : 8; @@ -114,7 +114,7 @@ struct pt_regs { unsigned int nested : 1; unsigned int __ssx_resv4 : 1; unsigned int instr_len : 4; - }; + } __packed; }; /* top of stack page */ }; > + unsigned short cs; /* CS selector proper */ Also, please put all those comments above the members, like the rest of the file does.
On Mon, Apr 10 2023 at 01:14, Xin Li wrote: > + union { > + unsigned long csx; /* cs extended: CS + any fields above it */ > + struct __attribute__((__packed__)) { > + unsigned short cs; /* CS selector proper */ > + unsigned int current_stack_level: 2; > + unsigned int __csx_resv1 : 6; > + unsigned int interrupt_shadowed : 1; > + unsigned int software_initiated : 1; > + unsigned int __csx_resv2 : 2; > + unsigned int nmi : 1; > + unsigned int __csx_resv3 : 3; > + unsigned int __csx_resv4 : 32; > + }; > + }; > unsigned long flags; > unsigned long sp; > - unsigned long ss; > + union { > + unsigned long ssx; /* ss extended: SS + any fields above it */ > + struct __attribute__((__packed__)) { > + unsigned short ss; /* SS selector proper */ > + unsigned int __ssx_resv1 : 16; > + unsigned int vector : 8; > + unsigned int __ssx_resv2 : 8; > + unsigned int type : 4; > + unsigned int __ssx_resv3 : 4; > + unsigned int enclv : 1; > + unsigned int long_mode : 1; > + unsigned int nested : 1; > + unsigned int __ssx_resv4 : 1; > + unsigned int instr_len : 4; > + }; > + }; This does not match section 5.2.1 Saving Information on the Regular Stack? of version 4 and later of the specification. Thanks, tglx
> > This does not match section > > 5.2.1 Saving Information on the Regular Stack? > > of version 4 and later of the specification. > Yes, this is correct. This patchset was posted in April, and once we got some very late requests for changes I asked Xin to hold off any further iterations until the spec had restabilized. -hpa
On Mon, Jun 05 2023 at 10:12, H. Peter Anvin wrote: >> >> This does not match section >> >> 5.2.1 Saving Information on the Regular Stack? >> >> of version 4 and later of the specification. >> > > Yes, this is correct. This patchset was posted in April, and once we got > some very late requests for changes I asked Xin to hold off any further > iterations until the spec had restabilized. I assumed that, but I stumbled over it when trying to review :)
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index d234ca797e4a..2429ad0df068 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -76,7 +76,7 @@ static void warn_bad_vsyscall(const char *level, struct pt_regs *regs, if (!show_unhandled_signals) return; - printk_ratelimited("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n", + printk_ratelimited("%s%s[%d] %s ip:%lx cs:%x sp:%lx ax:%lx si:%lx di:%lx\n", level, current->comm, task_pid_nr(current), message, regs->ip, regs->cs, regs->sp, regs->ax, regs->si, regs->di); diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index f4db78b09c8f..2abb23e6c1e2 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -82,12 +82,40 @@ struct pt_regs { * On hw interrupt, it's IRQ number: */ unsigned long orig_ax; -/* Return frame for iretq */ +/* Return frame for iretq/eretu/erets */ unsigned long ip; - unsigned long cs; + union { + unsigned long csx; /* cs extended: CS + any fields above it */ + struct __attribute__((__packed__)) { + unsigned short cs; /* CS selector proper */ + unsigned int current_stack_level: 2; + unsigned int __csx_resv1 : 6; + unsigned int interrupt_shadowed : 1; + unsigned int software_initiated : 1; + unsigned int __csx_resv2 : 2; + unsigned int nmi : 1; + unsigned int __csx_resv3 : 3; + unsigned int __csx_resv4 : 32; + }; + }; unsigned long flags; unsigned long sp; - unsigned long ss; + union { + unsigned long ssx; /* ss extended: SS + any fields above it */ + struct __attribute__((__packed__)) { + unsigned short ss; /* SS selector proper */ + unsigned int __ssx_resv1 : 16; + unsigned int vector : 8; + unsigned int __ssx_resv2 : 8; + unsigned int type : 4; + unsigned int __ssx_resv3 : 4; + unsigned int enclv : 1; + unsigned int long_mode : 1; + unsigned int nested : 1; + unsigned int __ssx_resv4 : 1; + unsigned int instr_len : 4; + }; + }; /* top of stack page */ }; diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index bb65a68b4b49..a1aa74864c8b 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -116,7 +116,7 @@ void __show_regs(struct pt_regs *regs, enum show_regs_mode mode, printk("%sFS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", log_lvl, fs, fsindex, gs, gsindex, shadowgs); - printk("%sCS: %04lx DS: %04x ES: %04x CR0: %016lx\n", + printk("%sCS: %04x DS: %04x ES: %04x CR0: %016lx\n", log_lvl, regs->cs, ds, es, cr0); printk("%sCR2: %016lx CR3: %016lx CR4: %016lx\n", log_lvl, cr2, cr3, cr4);