Bug 11562 (unplug)
Summary: | unpluggin a processor results in invalid context error | ||
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Product: | Platform Specific/Hardware | Reporter: | raz ben yehuda (raziebe) |
Component: | x86-64 | Assignee: | Mathieu Desnoyers (mathieu.desnoyers) |
Status: | CLOSED PATCH_ALREADY_AVAILABLE | ||
Severity: | normal | CC: | mathieu.desnoyers, raziebe |
Priority: | P1 | ||
Hardware: | All | ||
OS: | Linux | ||
Kernel Version: | 2.6.26.5 | Subsystem: | |
Regression: | Yes | Bisected commit-id: |
Description
raz ben yehuda
2008-09-13 03:56:18 UTC
I'll reassign this regression to x86 - looks like something borked in the smp->up text rewriting. already patched and posted to LKML. simply replaced the spinlock with a semaphore. On Sat, Sep 13, 2008 at 8:14 PM, <bugme-daemon@bugzilla.kernel.org> wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=11562 > > > akpm@osdl.org changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > AssignedTo|acpi_other@kernel- |platform_x86_64@kernel- > |bugs.osdl.org |bugs.osdl.org > Component|Other |x86-64 > Product|ACPI |Platform Specific/Hardware > Regression|0 |1 > > > > > ------- Comment #1 from akpm@osdl.org 2008-09-13 11:14 ------- > I'll reassign this regression to x86 - looks like something borked > in the smp->up text rewriting. > > > -- > Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email > ------- You are receiving this mail because: ------- > You are on the CC list for the bug, or are watching someone who is. > You reported the bug, or are watching the reporter. > We vmap two RW pages in text_poke to make sure we can write to the kernel text, even if it is read-only. Two possible solutions : - either we use a 2 pages fixmap, so we don't have to use vmap. - We find out why the cpu hotplug code disables preemption or interrupts and fix that instead. I'll be traveling next week (kernel summit and plumber conf.), but I'll try to have a look soon. Mathieu On Sat, Sep 13, 2008 at 10:32 PM, <bugme-daemon@bugzilla.kernel.org> wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=11562 > > > mathieu.desnoyers@polymtl.ca changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |mathieu.desnoyers@polymtl.ca > > > > > ------- Comment #3 from mathieu.desnoyers@polymtl.ca 2008-09-13 13:32 > ------- > We vmap two RW pages in text_poke to make sure we can write to the > kernel text, even if it is read-only. Two possible solutions : > > - either we use a 2 pages fixmap, so we don't have to use vmap. > - We find out why the cpu hotplug code disables preemption or interrupts > and fix that instead. I simply replaced the spinlocks to semaphores. > I'll be traveling next week (kernel summit and plumber conf.), but I'll try > to > have a look soon. > > Mathieu > > > -- > Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email > ------- You are receiving this mail because: ------- > You are on the CC list for the bug, or are watching someone who is. > You reported the bug, or are watching the reporter. > Hrm, the comment from raz ben yehuda is right, 2.6.26 should include the fix already posted to LKML. The commit id of this fix in mainline is : 2f1dafe50cc4e58a239fd81bd47f87f32042a1ee I think some trivial patch modification will be needed to apply it to 2.6.26. Probably the original patch I posted on LKML would apply better : http://lkml.org/lkml/2008/4/19/139 Can you try either of these two and see if it fixes the issue ? If it does, then the fix should be merged to 2.6.26.x. Thanks, Mathieu |