From: Borislav Petkov <bp@alien8.de>
To: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: luto@kernel.org, tglx@linutronix.de, mingo@kernel.org,
x86@kernel.org, len.brown@intel.com, dave.hansen@intel.com,
thiago.macieira@intel.com, jing2.liu@intel.com,
ravi.v.shankar@intel.com, linux-kernel@vger.kernel.org,
kvm@vger.kernel.org
Subject: Re: [PATCH v9 05/26] x86/fpu/xstate: Add new variables to indicate dynamic XSTATE buffer size
Date: Thu, 12 Aug 2021 17:03:15 +0200 [thread overview]
Message-ID: <YRU4M6FO0OHc67Wx@zn.tnic> (raw)
In-Reply-To: <20210730145957.7927-6-chang.seok.bae@intel.com>
On Fri, Jul 30, 2021 at 07:59:36AM -0700, Chang S. Bae wrote:
> @@ -167,8 +158,10 @@ static void __init fpu__init_task_struct_size(void)
> /*
> * Add back the dynamically-calculated register state
> * size.
> + *
> + * Use the minimum size as embedded to task_struct.
embedded in...
> diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
> index 74e608c6ad6c..12caf1a56ce0 100644
> --- a/arch/x86/kernel/fpu/xstate.c
> +++ b/arch/x86/kernel/fpu/xstate.c
> @@ -77,12 +77,51 @@ static unsigned int xstate_comp_offsets[XFEATURE_MAX] __ro_after_init =
> static unsigned int xstate_supervisor_only_offsets[XFEATURE_MAX] __ro_after_init =
> { [ 0 ... XFEATURE_MAX - 1] = -1};
>
> -/*
> - * The XSAVE area of kernel can be in standard or compacted format;
> - * it is always in standard format for user mode. This is the user
> - * mode standard format size used for signal and ptrace frames.
> +/**
> + * struct fpu_xstate_buffer_config - xstate buffer configuration
> + * @max_size: The CPUID-enumerated all-feature "maximum" size
> + * for xstate per-task buffer.
> + * @min_size: The size to fit into the statically-allocated
> + * buffer. With dynamic states, this buffer no longer
> + * contains all the enabled state components.
> + * @user_size: The size of user-space buffer for signal and
> + * ptrace frames, in the non-compacted format.
> */
> -unsigned int fpu_user_xstate_size __ro_after_init;
> +struct fpu_xstate_buffer_config {
> + unsigned int min_size, max_size;
> + unsigned int user_size;
> +};
> +
> +static struct fpu_xstate_buffer_config buffer_config __ro_after_init;
I know I had asked for the accessors below but if this is going to be
read-only after init and is not going to change for duration of the
system lifetime, then you don't really need those accessors.
I.e., you can do
struct fpu_xstate_buffer_config {
unsigned int min_size, max_size;
unsigned int user_size;
};
static struct fpu_xstate_buffer_config fpu_buf_cfg __ro_after_init;
and then access those values through fpu_buf_cfg.<value>
Thx.
> +
> +unsigned int get_xstate_config(enum xstate_config cfg)
> +{
> + switch (cfg) {
> + case XSTATE_MIN_SIZE:
> + return buffer_config.min_size;
> + case XSTATE_MAX_SIZE:
> + return buffer_config.max_size;
> + case XSTATE_USER_SIZE:
> + return buffer_config.user_size;
> + default:
> + return 0;
> + }
> +}
> +EXPORT_SYMBOL_GPL(get_xstate_config);
> +
> +void set_xstate_config(enum xstate_config cfg, unsigned int value)
> +{
> + switch (cfg) {
> + case XSTATE_MIN_SIZE:
> + buffer_config.min_size = value;
> + break;
> + case XSTATE_MAX_SIZE:
> + buffer_config.max_size = value;
> + break;
> + case XSTATE_USER_SIZE:
> + buffer_config.user_size = value;
> + }
> +}
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2021-08-12 15:02 UTC|newest]
Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-30 14:59 [PATCH v9 00/26] x86: Support Intel Advanced Matrix Extensions Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 01/26] x86/fpu/xstate: Modify the initialization helper to handle both static and dynamic buffers Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 02/26] x86/fpu/xstate: Modify state copy helpers " Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 03/26] x86/fpu/xstate: Modify address finders " Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 04/26] x86/fpu/xstate: Add a new variable to indicate dynamic user states Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 05/26] x86/fpu/xstate: Add new variables to indicate dynamic XSTATE buffer size Chang S. Bae
2021-08-12 15:03 ` Borislav Petkov [this message]
2021-07-30 14:59 ` [PATCH v9 06/26] x86/fpu/xstate: Calculate and remember dynamic XSTATE buffer sizes Chang S. Bae
2021-08-12 16:36 ` Borislav Petkov
2021-07-30 14:59 ` [PATCH v9 07/26] x86/fpu/xstate: Convert the struct fpu 'state' field to a pointer Chang S. Bae
2021-08-12 17:09 ` Borislav Petkov
2021-07-30 14:59 ` [PATCH v9 08/26] x86/fpu/xstate: Introduce helpers to manage the XSTATE buffer dynamically Chang S. Bae
2021-08-12 19:44 ` Borislav Petkov
2021-08-13 8:04 ` Bae, Chang Seok
2021-08-13 10:04 ` Borislav Petkov
2021-08-13 19:43 ` Bae, Chang Seok
2021-08-18 9:28 ` Borislav Petkov
2021-08-18 19:46 ` Bae, Chang Seok
2021-08-25 16:01 ` Bae, Chang Seok
2021-08-30 17:07 ` Borislav Petkov
2021-08-30 23:39 ` Bae, Chang Seok
2021-08-16 18:33 ` Bae, Chang Seok
2021-08-16 18:53 ` Borislav Petkov
2021-08-30 17:45 ` Dave Hansen
2021-08-30 23:39 ` Bae, Chang Seok
2021-07-30 14:59 ` [PATCH v9 09/26] x86/fpu/xstate: Update the XSTATE save function to support dynamic states Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 10/26] x86/fpu/xstate: Update the XSTATE buffer address finder " Chang S. Bae
2021-08-18 11:33 ` Borislav Petkov
2021-08-18 19:47 ` Bae, Chang Seok
2021-08-30 17:18 ` Borislav Petkov
2021-08-30 23:38 ` Bae, Chang Seok
2021-07-30 14:59 ` [PATCH v9 11/26] x86/fpu/xstate: Update the XSTATE context copy function " Chang S. Bae
2021-08-18 12:03 ` Borislav Petkov
2021-08-18 19:47 ` Bae, Chang Seok
2021-07-30 14:59 ` [PATCH v9 12/26] x86/fpu/xstate: Use feature disable (XFD) to protect dynamic user state Chang S. Bae
2021-08-18 16:24 ` Borislav Petkov
2021-08-18 17:20 ` Thiago Macieira
2021-08-18 17:46 ` Borislav Petkov
2021-08-18 17:58 ` Thiago Macieira
2021-08-18 18:10 ` Borislav Petkov
2021-08-24 22:51 ` Len Brown
2021-08-18 20:43 ` Bae, Chang Seok
2021-08-18 21:04 ` Thiago Macieira
2021-08-18 21:12 ` Bae, Chang Seok
2021-08-18 22:27 ` Thiago Macieira
2021-08-19 1:21 ` Andy Lutomirski
2021-08-19 16:06 ` Thiago Macieira
2021-08-18 21:17 ` Borislav Petkov
2021-08-18 21:37 ` Bae, Chang Seok
2021-08-19 8:00 ` Borislav Petkov
2021-08-19 15:24 ` Bae, Chang Seok
2021-08-24 23:22 ` Len Brown
2021-08-30 17:31 ` Borislav Petkov
2021-09-17 3:48 ` Len Brown
2021-08-18 19:47 ` Bae, Chang Seok
2021-08-24 22:21 ` Len Brown
2021-08-30 17:41 ` Borislav Petkov
2021-08-31 21:44 ` Len Brown
2021-08-24 23:17 ` Len Brown
2021-08-30 17:53 ` Borislav Petkov
2021-08-31 22:07 ` Len Brown
2021-08-31 22:11 ` Dave Hansen
2021-08-30 18:04 ` Dave Hansen
2021-08-31 22:15 ` Len Brown
2021-08-31 22:16 ` Len Brown
2021-08-31 22:39 ` Thiago Macieira
2021-08-31 22:44 ` Len Brown
2021-07-30 14:59 ` [PATCH v9 13/26] x86/fpu/xstate: Support ptracer-induced XSTATE buffer expansion Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 14/26] x86/arch_prctl: Create ARCH_SET_STATE_ENABLE/ARCH_GET_STATE_ENABLE Chang S. Bae
2021-08-06 16:46 ` Thiago Macieira
2021-08-09 22:08 ` Bae, Chang Seok
2021-08-09 23:42 ` Thiago Macieira
2021-08-10 0:57 ` Bae, Chang Seok
2021-08-13 19:44 ` Bae, Chang Seok
2021-07-30 14:59 ` [PATCH v9 15/26] x86/fpu/xstate: Support both legacy and expanded signal XSTATE size Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 16/26] x86/fpu/xstate: Adjust the XSAVE feature table to address gaps in state component numbers Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 17/26] x86/fpu/xstate: Disable XSTATE support if an inconsistent state is detected Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 18/26] x86/cpufeatures/amx: Enumerate Advanced Matrix Extension (AMX) feature bits Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 19/26] x86/fpu/amx: Define AMX state components and have it used for boot-time checks Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 20/26] x86/fpu/amx: Initialize child's AMX state Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 21/26] x86/fpu/amx: Enable the AMX feature in 64-bit mode Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 22/26] x86/fpu/xstate: Skip writing zeros to signal frame for dynamic user states if in INIT-state Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 23/26] selftest/x86/amx: Test cases for the AMX state management Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 24/26] x86/insn/amx: Add TILERELEASE instruction to the opcode map Chang S. Bae
2021-07-30 14:59 ` [PATCH v9 25/26] intel_idle/amx: Add SPR support with XTILEDATA capability Chang S. Bae
2021-07-30 18:41 ` Dave Hansen
2021-08-03 21:32 ` Bae, Chang Seok
2021-08-03 21:38 ` Dave Hansen
2021-08-03 21:43 ` Brown, Len
2021-07-30 20:15 ` Dave Hansen
2021-07-30 14:59 ` [PATCH v9 26/26] x86/fpu/xstate: Add a sanity check for XFD state when saving XSTATE Chang S. Bae
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