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| author |   Michal Hocko <mhocko@suse.com> | 2018-11-13 19:49:10 +0100 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2018-12-11 11:46:13 +0100 |
| commit | 5b5e4d623ec8a34689df98e42d038a3b594d2ff9 (patch) | |
| tree | 07a91d5157c330a4ca7596d7c657e7f0af049375 /arch/x86/mm/init.c | |
| parent | x86/speculation: Change misspelled STIPB to STIBP (diff) | |
| download | linux-dev-5b5e4d623ec8a34689df98e42d038a3b594d2ff9.tar.xz linux-dev-5b5e4d623ec8a34689df98e42d038a3b594d2ff9.zip | |
x86/speculation/l1tf: Drop the swap storage limit restriction when l1tf=off
Swap storage is restricted to max_swapfile_size (~16TB on x86_64) whenever
the system is deemed affected by L1TF vulnerability. Even though the limit
is quite high for most deployments it seems to be too restrictive for
deployments which are willing to live with the mitigation disabled.
We have a customer to deploy 8x 6,4TB PCIe/NVMe SSD swap devices which is
clearly out of the limit.
Drop the swap restriction when l1tf=off is specified. It also doesn't make
much sense to warn about too much memory for the l1tf mitigation when it is
forcefully disabled by the administrator.
[ tglx: Folded the documentation delta change ]
Fixes: 377eeaa8e11f ("x86/speculation/l1tf: Limit swap file size to MAX_PA/2")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: <linux-mm@kvack.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181113184910.26697-1-mhocko@kernel.org
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index ef99f3892e1f..427a955a2cf2 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -931,7 +931,7 @@ unsigned long max_swapfile_size(void) pages = generic_max_swapfile_size(); - if (boot_cpu_has_bug(X86_BUG_L1TF)) { + if (boot_cpu_has_bug(X86_BUG_L1TF) && l1tf_mitigation != L1TF_MITIGATION_OFF) { /* Limit the swap file size to MAX_PA/2 for L1TF workaround */ unsigned long long l1tf_limit = l1tf_pfn_limit(); /* |