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<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>u-boot's
bootelf clears (memset to 0) sections of SHT_NOBITS type. This covers .bss
sections – however, it might also includes other sections, not expected
to be cleared as per some users expectations (stacks, for example).<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>I
am beginning to wonder if this behavior is correct/desired: if one tries to
bootelf an ELF file which happens to resizde somewhere inside the .bss section,
or some other data section of the loaded code, bootelf clears it (or part of it…)
while loading, corrupting the code to be loaded.<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>AFAIK,
.bss is normally zeroed out in crt0 (or equivalent), so there is no need (?) to
zero it in bootelf. Bootelf may also defer all such actions (clearing section)
to the end of the loading process.<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>Please
feel free to correct me I I am wrong…<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'>
<st1:PersonName w:st="on">Baruch Cochavy</st1:PersonName><o:p></o:p></span></font></p>
<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=3 face=Arial><span style='font-size:12.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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