From: Andy Lutomirski <luto@kernel.org> To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov <bp@alien8.de>, Linus Torvalds <torvalds@linux-foundation.org>, Andrew Morton <akpm@linux-foundation.org>, Mel Gorman <mgorman@suse.de>, "linux-mm@kvack.org" <linux-mm@kvack.org>, Nadav Amit <nadav.amit@gmail.com>, Rik van Riel <riel@redhat.com>, Dave Hansen <dave.hansen@intel.com>, Arjan van de Ven <arjan@linux.intel.com>, Peter Zijlstra <peterz@infradead.org>, Andy Lutomirski <luto@kernel.org> Subject: [PATCH v4 08/10] x86/mm: Add nopcid to turn off PCID Date: Thu, 29 Jun 2017 08:53:20 -0700 [thread overview] Message-ID: <8bbb2e65bcd249a5f18bfb8128b4689f08ac2b60.1498751203.git.luto@kernel.org> (raw) In-Reply-To: <cover.1498751203.git.luto@kernel.org> In-Reply-To: <cover.1498751203.git.luto@kernel.org> The parameter is only present on x86_64 systems to save a few bytes, as PCID is always disabled on x86_32. Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> --- Documentation/admin-guide/kernel-parameters.txt | 2 ++ arch/x86/kernel/cpu/common.c | 18 ++++++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7737ab5d04b2..705666a44ba2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2648,6 +2648,8 @@ nopat [X86] Disable PAT (page attribute table extension of pagetables) support. + nopcid [X86-64] Disable the PCID cpu feature. + norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c8b39870f33e..904485e7b230 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -168,6 +168,24 @@ static int __init x86_mpx_setup(char *s) } __setup("nompx", x86_mpx_setup); +#ifdef CONFIG_X86_64 +static int __init x86_pcid_setup(char *s) +{ + /* require an exact match without trailing characters */ + if (strlen(s)) + return 0; + + /* do not emit a message if the feature is not present */ + if (!boot_cpu_has(X86_FEATURE_PCID)) + return 1; + + setup_clear_cpu_cap(X86_FEATURE_PCID); + pr_info("nopcid: PCID feature disabled\n"); + return 1; +} +__setup("nopcid", x86_pcid_setup); +#endif + static int __init x86_noinvpcid_setup(char *s) { /* noinvpcid doesn't accept parameters */ -- 2.9.4
WARNING: multiple messages have this Message-ID (diff)
From: Andy Lutomirski <luto@kernel.org> To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov <bp@alien8.de>, Linus Torvalds <torvalds@linux-foundation.org>, Andrew Morton <akpm@linux-foundation.org>, Mel Gorman <mgorman@suse.de>, "linux-mm@kvack.org" <linux-mm@kvack.org>, Nadav Amit <nadav.amit@gmail.com>, Rik van Riel <riel@redhat.com>, Dave Hansen <dave.hansen@intel.com>, Arjan van de Ven <arjan@linux.intel.com>, Peter Zijlstra <peterz@infradead.org>, Andy Lutomirski <luto@kernel.org> Subject: [PATCH v4 08/10] x86/mm: Add nopcid to turn off PCID Date: Thu, 29 Jun 2017 08:53:20 -0700 [thread overview] Message-ID: <8bbb2e65bcd249a5f18bfb8128b4689f08ac2b60.1498751203.git.luto@kernel.org> (raw) In-Reply-To: <cover.1498751203.git.luto@kernel.org> In-Reply-To: <cover.1498751203.git.luto@kernel.org> The parameter is only present on x86_64 systems to save a few bytes, as PCID is always disabled on x86_32. Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> --- Documentation/admin-guide/kernel-parameters.txt | 2 ++ arch/x86/kernel/cpu/common.c | 18 ++++++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7737ab5d04b2..705666a44ba2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2648,6 +2648,8 @@ nopat [X86] Disable PAT (page attribute table extension of pagetables) support. + nopcid [X86-64] Disable the PCID cpu feature. + norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c8b39870f33e..904485e7b230 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -168,6 +168,24 @@ static int __init x86_mpx_setup(char *s) } __setup("nompx", x86_mpx_setup); +#ifdef CONFIG_X86_64 +static int __init x86_pcid_setup(char *s) +{ + /* require an exact match without trailing characters */ + if (strlen(s)) + return 0; + + /* do not emit a message if the feature is not present */ + if (!boot_cpu_has(X86_FEATURE_PCID)) + return 1; + + setup_clear_cpu_cap(X86_FEATURE_PCID); + pr_info("nopcid: PCID feature disabled\n"); + return 1; +} +__setup("nopcid", x86_pcid_setup); +#endif + static int __init x86_noinvpcid_setup(char *s) { /* noinvpcid doesn't accept parameters */ -- 2.9.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2017-06-29 15:54 UTC|newest] Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-06-29 15:53 [PATCH v4 00/10] PCID and improved laziness Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 01/10] x86/mm: Don't reenter flush_tlb_func_common() Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-06-30 13:11 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 02/10] x86/mm: Delete a big outdated comment about TLB flushing Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-06-30 13:11 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 03/10] x86/mm: Give each mm TLB flush generation a unique ID Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:31 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-07-05 10:58 ` Peter Zijlstra 2017-06-29 15:53 ` [PATCH v4 04/10] x86/mm: Track the TLB's tlb_gen and update the flushing algorithm Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:31 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 05/10] x86/mm: Rework lazy TLB mode and TLB freshness tracking Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:31 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 06/10] x86/mm: Stop calling leave_mm() in idle code Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:32 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 07/10] x86/mm: Disable PCID on 32-bit kernels Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:32 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski [this message] 2017-06-29 15:53 ` [PATCH v4 08/10] x86/mm: Add nopcid to turn off PCID Andy Lutomirski 2017-07-05 10:32 ` [tip:x86/mm] x86/mm: Add the 'nopcid' boot option " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 09/10] x86/mm: Enable CR4.PCIDE on supported systems Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-05 10:33 ` [tip:x86/mm] " tip-bot for Andy Lutomirski 2017-06-29 15:53 ` [PATCH v4 10/10] x86/mm: Try to preserve old TLB entries using PCID Andy Lutomirski 2017-06-29 15:53 ` Andy Lutomirski 2017-07-03 10:56 ` Thomas Gleixner 2017-07-03 10:56 ` Thomas Gleixner 2017-07-05 12:18 ` Peter Zijlstra 2017-07-05 12:18 ` Peter Zijlstra 2017-07-05 16:04 ` Andy Lutomirski 2017-07-05 16:04 ` Andy Lutomirski 2017-07-05 17:02 ` Peter Zijlstra 2017-07-05 17:02 ` Peter Zijlstra 2017-07-18 8:53 ` Ingo Molnar 2017-07-18 8:53 ` Ingo Molnar 2017-07-18 17:06 ` Andy Lutomirski 2017-07-18 17:06 ` Andy Lutomirski 2017-07-05 12:25 ` Peter Zijlstra 2017-07-05 12:25 ` Peter Zijlstra 2017-07-05 16:10 ` Andy Lutomirski 2017-07-05 16:10 ` Andy Lutomirski 2017-07-28 13:49 ` Peter Zijlstra 2017-07-28 13:49 ` Peter Zijlstra 2017-06-30 12:44 ` [PATCH v4 00/10] PCID and improved laziness Matt Fleming 2017-06-30 12:44 ` Matt Fleming 2017-07-11 11:32 ` Matt Fleming 2017-07-11 11:32 ` Matt Fleming 2017-07-11 15:00 ` Andy Lutomirski 2017-07-11 15:00 ` Andy Lutomirski 2017-07-13 19:36 ` Matt Fleming 2017-07-13 19:36 ` Matt Fleming 2017-07-05 8:56 ` Ingo Molnar 2017-07-05 8:56 ` Ingo Molnar 2017-07-05 16:53 ` Linus Torvalds 2017-07-05 16:53 ` Linus Torvalds 2017-07-17 9:57 ` Mel Gorman 2017-07-17 9:57 ` Mel Gorman 2017-07-17 15:06 ` Ingo Molnar 2017-07-17 15:06 ` Ingo Molnar 2017-07-17 15:56 ` Mel Gorman 2017-07-17 15:56 ` Mel Gorman [not found] ` <CALBSrqDW6pGjHxOmzfnkY_KoNeH6F=pTb8-tJ8r-zbu4prw9HQ@mail.gmail.com> 2017-09-12 19:32 ` Sai Praneeth Prakhya 2017-09-12 19:32 ` Sai Praneeth Prakhya 2017-09-12 19:45 ` Andy Lutomirski 2017-09-12 20:28 ` Prakhya, Sai Praneeth 2017-09-13 7:43 ` Ingo Molnar 2017-09-13 7:43 ` Ingo Molnar 2017-09-13 7:45 ` Ingo Molnar 2017-09-13 7:45 ` Ingo Molnar 2017-09-13 4:14 ` Sai Praneeth Prakhya 2017-09-13 4:14 ` Sai Praneeth Prakhya
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