Merge branch 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull MCE changes from Ingo Molnar.

* 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix return value of mce_chrdev_read() when erst is disabled
  x86/mce: Convert static array of pointers to per-cpu variables
  x86/mce: Replace hard coded hex constants with symbolic defines
  x86/mce: Recognise machine check bank signature for data path error
  x86/mce: Handle "action required" errors
  x86/mce: Add mechanism to safely save information in MCE handler
  x86/mce: Create helper function to save addr/misc when needed
  HWPOISON: Add code to handle "action required" errors.
  HWPOISON: Clean up memory_failure() vs. __memory_failure()
This commit is contained in:
Linus Torvalds
2012-03-22 09:42:04 -07:00
9 changed files with 221 additions and 117 deletions

View File

@@ -187,33 +187,40 @@ int hwpoison_filter(struct page *p)
EXPORT_SYMBOL_GPL(hwpoison_filter);
/*
* Send all the processes who have the page mapped an ``action optional''
* signal.
* Send all the processes who have the page mapped a signal.
* ``action optional'' if they are not immediately affected by the error
* ``action required'' if error happened in current execution context
*/
static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
unsigned long pfn, struct page *page)
static int kill_proc(struct task_struct *t, unsigned long addr, int trapno,
unsigned long pfn, struct page *page, int flags)
{
struct siginfo si;
int ret;
printk(KERN_ERR
"MCE %#lx: Killing %s:%d early due to hardware memory corruption\n",
"MCE %#lx: Killing %s:%d due to hardware memory corruption\n",
pfn, t->comm, t->pid);
si.si_signo = SIGBUS;
si.si_errno = 0;
si.si_code = BUS_MCEERR_AO;
si.si_addr = (void *)addr;
#ifdef __ARCH_SI_TRAPNO
si.si_trapno = trapno;
#endif
si.si_addr_lsb = compound_trans_order(compound_head(page)) + PAGE_SHIFT;
/*
* Don't use force here, it's convenient if the signal
* can be temporarily blocked.
* This could cause a loop when the user sets SIGBUS
* to SIG_IGN, but hopefully no one will do that?
*/
ret = send_sig_info(SIGBUS, &si, t); /* synchronous? */
if ((flags & MF_ACTION_REQUIRED) && t == current) {
si.si_code = BUS_MCEERR_AR;
ret = force_sig_info(SIGBUS, &si, t);
} else {
/*
* Don't use force here, it's convenient if the signal
* can be temporarily blocked.
* This could cause a loop when the user sets SIGBUS
* to SIG_IGN, but hopefully no one will do that?
*/
si.si_code = BUS_MCEERR_AO;
ret = send_sig_info(SIGBUS, &si, t); /* synchronous? */
}
if (ret < 0)
printk(KERN_INFO "MCE: Error sending signal to %s:%d: %d\n",
t->comm, t->pid, ret);
@@ -338,8 +345,9 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
* Also when FAIL is set do a force kill because something went
* wrong earlier.
*/
static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
int fail, struct page *page, unsigned long pfn)
static void kill_procs(struct list_head *to_kill, int doit, int trapno,
int fail, struct page *page, unsigned long pfn,
int flags)
{
struct to_kill *tk, *next;
@@ -363,8 +371,8 @@ static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
* check for that, but we need to tell the
* process anyways.
*/
else if (kill_proc_ao(tk->tsk, tk->addr, trapno,
pfn, page) < 0)
else if (kill_proc(tk->tsk, tk->addr, trapno,
pfn, page, flags) < 0)
printk(KERN_ERR
"MCE %#lx: Cannot send advisory machine check signal to %s:%d\n",
pfn, tk->tsk->comm, tk->tsk->pid);
@@ -844,7 +852,7 @@ static int page_action(struct page_state *ps, struct page *p,
* the pages and send SIGBUS to the processes if the data was dirty.
*/
static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
int trapno)
int trapno, int flags)
{
enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS;
struct address_space *mapping;
@@ -962,8 +970,8 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
* use a more force-full uncatchable kill to prevent
* any accesses to the poisoned memory.
*/
kill_procs_ao(&tokill, !!PageDirty(ppage), trapno,
ret != SWAP_SUCCESS, p, pfn);
kill_procs(&tokill, !!PageDirty(ppage), trapno,
ret != SWAP_SUCCESS, p, pfn, flags);
return ret;
}
@@ -984,7 +992,25 @@ static void clear_page_hwpoison_huge_page(struct page *hpage)
ClearPageHWPoison(hpage + i);
}
int __memory_failure(unsigned long pfn, int trapno, int flags)
/**
* memory_failure - Handle memory failure of a page.
* @pfn: Page Number of the corrupted page
* @trapno: Trap number reported in the signal to user space.
* @flags: fine tune action taken
*
* This function is called by the low level machine check code
* of an architecture when it detects hardware memory corruption
* of a page. It tries its best to recover, which includes
* dropping pages, killing processes etc.
*
* The function is primarily of use for corruptions that
* happen outside the current execution context (e.g. when
* detected by a background scrubber)
*
* Must run in process context (e.g. a work queue) with interrupts
* enabled and no spinlocks hold.
*/
int memory_failure(unsigned long pfn, int trapno, int flags)
{
struct page_state *ps;
struct page *p;
@@ -1130,7 +1156,7 @@ int __memory_failure(unsigned long pfn, int trapno, int flags)
* Now take care of user space mappings.
* Abort on fail: __delete_from_page_cache() assumes unmapped page.
*/
if (hwpoison_user_mappings(p, pfn, trapno) != SWAP_SUCCESS) {
if (hwpoison_user_mappings(p, pfn, trapno, flags) != SWAP_SUCCESS) {
printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
res = -EBUSY;
goto out;
@@ -1156,29 +1182,7 @@ out:
unlock_page(hpage);
return res;
}
EXPORT_SYMBOL_GPL(__memory_failure);
/**
* memory_failure - Handle memory failure of a page.
* @pfn: Page Number of the corrupted page
* @trapno: Trap number reported in the signal to user space.
*
* This function is called by the low level machine check code
* of an architecture when it detects hardware memory corruption
* of a page. It tries its best to recover, which includes
* dropping pages, killing processes etc.
*
* The function is primarily of use for corruptions that
* happen outside the current execution context (e.g. when
* detected by a background scrubber)
*
* Must run in process context (e.g. a work queue) with interrupts
* enabled and no spinlocks hold.
*/
void memory_failure(unsigned long pfn, int trapno)
{
__memory_failure(pfn, trapno, 0);
}
EXPORT_SYMBOL_GPL(memory_failure);
#define MEMORY_FAILURE_FIFO_ORDER 4
#define MEMORY_FAILURE_FIFO_SIZE (1 << MEMORY_FAILURE_FIFO_ORDER)
@@ -1251,7 +1255,7 @@ static void memory_failure_work_func(struct work_struct *work)
spin_unlock_irqrestore(&mf_cpu->lock, proc_flags);
if (!gotten)
break;
__memory_failure(entry.pfn, entry.trapno, entry.flags);
memory_failure(entry.pfn, entry.trapno, entry.flags);
}
}